| Prefix | Brand | Product line | Characteristics | Description |
|---|---|---|---|---|
| 10X | SNR | Spherical roller bearings | Dimension | Non-ISO dimensions |
| 2- | NTN | Ball bearings | Component | Concerns inner ring & outer ring only |
| 2LA | NTN | High precision angular contact ball bearings | Material | Special material with improved surface treatment |
| 2TS2- | NTN | Tapered roller bearings | Material | Heat treatment for operation up to 160°C, for the cone and the cup |
| 4T- | NTN | Tapered roller bearings | Material | Case hardened steel, a2 = 1.4 & interchangeability |
| 5- | NTN | Ball bearings | Component | Concerns balls only |
| 5S | NTN | High precision angular contact ball bearings | Component | Hybrid bearing, steel rings and ceramic balls |
| 7E- | NTN | Needle roller bearings | Material | Case hardened outer ring |
| 7MC3- | NTN | Ball bearings | Others | Ceramic coated outer ring |
| 7MP- | NTN | Ball bearings | Others | Plastic molded outer ring |
| 8E- | NTN | Needle roller bearings | Component | Case hardened rings (if massive rings) or cage (if needle and cage assembly) |
| 8Q- | NTN | Needle roller bearings | Component | Nitrided cage |
| A- | NTN | Bearing units | Assembly | Bearing insert outer ring: opposite mounting to inner ring |
| AC- | NTN | Ball bearings | Others | Anti-creeping bearing |
| AH | NTN | Bearing units | Others | Bearing insert with hexagon bore. AH is basic number. e.g. 1AH03-9/16 |
| AS | NTN | Bearing units | Others | Bearing insert with square bore. AS is basic number. e.g. 1AS08-7/8 |
| B- | NTN | Bearing units | Assembly | Bearing insert: 180° mounting to housing |
| BNS | NTN | High precision angular contact ball bearings | Others | High precision angular contact bearings for high speeds, double sided non-contact seal |
| C | SNR | Bearing units | Dimension | Bearing insert with cylindrical outer ring matching JIS norm |
| C- | NTN | Bearing units | Component | Bearing unit with cast iron cover (open version) |
| CH | SNR | Tapered roller bearings | Component | Ceramic rolling elements |
| CH | SNR | High precision angular contact ball bearings | Component | Hybrid bearing, steel rings and ceramic balls |
| CM- | NTN | Bearing units | Component | Bearing unit with cast iron cover (closed version) |
| D- | SNR | Bearing units | Material | Ductile housing with standard dimensions (design optimized) |
| E- | NTN | Tapered roller bearings | Material | Bearing with carburized rings and rollers |
| EA- | NTN | Tapered roller bearings | Material | E- case hardened steel + carbonitriding |
| EC- | NTN | Ball bearings | Others | Expansion adjustment bearing for general purpose |
| EC1- | NTN | Ball bearings | Others | Expansion adjustment bearing for high temperature (maxi 150°C) |
| EC2- | NTN | Ball bearings | Others | Expansion adjustment bearing for ultra high temperature (maxi 180°C) |
| ECO- | NTN | Tapered roller bearings | Material | ECO Top bearing (ETA- steel + optimized internal design) & interchangeability |
| EH | NTN | Tapered roller bearings | Dimension | Extra heavy series |
| EL | NTN | Tapered roller bearings | Dimension | Extra light series |
| ET- | NTN | Tapered roller bearings | Material | High quality case hardened steel a2 = 1.9 & interchangeability |
| ETA- | NTN | Tapered roller bearings | Material | High quality case hardened steel with carbonitriding, a2=2.8 & interchangeability |
| F- | NTN | Ball bearings | Material | Stainless steel ball bearing |
| FXX | SNR | Tapered roller bearings | Dimension | Modified width for outer ring |
| H | NTN | Tapered roller bearings | Dimension | Heavy series |
| HH | NTN | Tapered roller bearings | Dimension | Heavier than heavy series |
| HL- | NTN | Tapered roller bearings | Dimension | HL treatment on the rollers |
| HL- | NTN | Needle roller bearings | Material | Special needles for better lubrication |
| HM | NTN | Tapered roller bearings | Dimension | Heavy medium series |
| HSE | NTN | High precision angular contact ball bearings | Others | High precision angular contact bearings for high speeds |
| HSF | NTN | High precision angular contact ball bearings | Others | High precision angular contact bearings for super high speed |
| J | NTN | Tapered roller bearings | Dimension | J-Line metric series Belong to ABMA norm. Can be associated with all other ABMA prefix (EL,EH,H,HH,HM,M,LM,L,LL) |
| L | NTN | Tapered roller bearings | Dimension | Light series |
| LL | NTN | Tapered roller bearings | Dimension | Lighter than light series |
| LM | NTN | Tapered roller bearings | Dimension | Light Medium series |
| M | NTN | Tapered roller bearings | Dimension | Medium series |
| M- | NTN | Bearing units | Material | Bearing insert inner ring: black oxide coating |
| ML | SNR | High precision angular contact ball bearings | Others | High precision angular contact bearings for high speeds |
| MLCH | SNR | High precision angular contact ball bearings | Others | High precision angular contact bearings with ceramic balls for high speeds |
| MLE | SNR | High precision angular contact ball bearings | Others | High precision angular contact bearings for high speeds, double sided non-contact seal |
| MLECH | SNR | High precision angular contact ball bearings | Others | High precision angular contact bearings with ceramic balls for high speeds, double sided non-contact seal |
| R- | NTN | Ball bearings | Dimension | Inch dimensions |
| S | SNR | Ball bearings | Material | Stainless steel ball bearing |
| S | SNR | Bearing units | Material | Stainless steel type |
| S- | NTN | Ball bearings | Material | Ceramic material |
| S- | NTN | Bearing units | Component | Bearing unit with steel cover (open version) |
| SM- | NTN | Bearing units | Component | Bearing unit with steel cover (closed version) |
| T7FC | NTN | Tapered roller bearings | Others | Steeper angle |
| TA- / TAB- | NTN | Ball bearings | Material | Made of nitride treated bearing steel |
| TM- / TMB- | NTN | Ball bearings | Material | Made of bearing steel with special thermal treatment |
| TS2- | NTN | Tapered roller bearings | Material | Heat treatment for operation up to 160°C, for all bearing elements |
| TS2- | NTN | Ball bearings | Material | Special thermal treatment up to 160°C |
| TS3- | NTN | Ball bearings | Material | Special thermal treatment up to 200°C |
| TS4- | NTN | Ball bearings | Material | Special thermal treatment up to 250°C |
| U-RSH | NTN | Ball bearings | Others | Sensor bearing |
| W- | NTN | Ball bearings | Dimension | Modified width |
| WA | NTN | Spherical roller bearings | Dimension | Non-ISO dimensions |
| X | SNR | Bearing units | Others | Bearing insert without shaft fixation |
| Z | SNR | Bearing units | Others | Bearing insert for food processing industry |
| Suffix | Brand | Product line | Characteristics | Description |
|---|---|---|---|---|
| /2AS | NTN | Needle roller bearings | Component | Grease Shell Alvania 2 |
| /3AS | NTN | Needle roller bearings | Component | Grease Shell Alvania 3 |
| /5K | NTN | Needle roller bearings | Component | Grease Multemp SRL |
| /8A | NTN | Needle roller bearings | Component | Grease Alvania EP2 |
| /GH | NTN | Ball bearings | Design | Heavy preload |
| /GL | NTN | Ball bearings | Design | Light preload |
| /GM | NTN | Ball bearings | Design | Medium preload |
| /GN | NTN | Ball bearings | Design | Standard preload |
| /L588 | NTN | Needle roller bearings | Component | Pyronoc Universal N6C |
| /LP03 | NTN | Needle roller bearings | Component | Solid Lubrication |
| 2AS | NTN | Ball bearings | Component | Standard grease for sealed and shielded bearings (-25°C up to +120°C) |
| 2RS | SNR | Ball bearings | Component | Contact seal on both sides - Only for stainless steel deep groove ball bearings |
| 5K | NTN | Ball bearings | Component | Universal grease for sealed and shielded bearings (-40°C up to +150°C) |
| A | NTN | Tapered roller bearings | Design | Internal design change (for inch items only) |
| A | SNR | Tapered roller bearings | Dimension | Conform to ISO and optimized capacity |
| A | SNR | Ball bearings | Component | 1 row angular contact ball bearings: Polyamide cage |
| A | SNR | Ball bearings | Design | Double row angular contact ball bearings : PA66 + flass fiber cage ; 25° contact angle ; no filling slot Double row deep groove ball bearings: PA66 + flass fiber cage ; no filling slot |
| A | SNR | Ball bearings | Design | Double row angular contact ball bearings : PA66 + flass fiber cage ; 25° contact angle ; no filling slot Double row deep groove ball bearings: PA66 + flass fiber cage ; no filling slot |
| A | NTN | Ball bearings | Component | Seal made of Polyacryl material |
| A, B, C | NTN | Needle roller bearings | Design | Internal design modified |
| A1 | NTN | Ball bearings | Component | Seal made of Fluorine material |
| A10 | SNR | Bearing units | Design | Standard housing without grease bore |
| A2 | NTN | Ball bearings | Component | Seal made of Silicon material |
| AD | NTN | High precision angular contact ball bearings | Design | Contact angle 25° |
| AGR | SNR | Bearing units | Component | Bearing insert with high performance seal for agriculture machines |
| B | NTN | Tapered roller bearings | Design | Internal modification (for inch items only) |
| B | NTN | Spherical roller bearings | Design | Non Ultage internal design, asymmetrical rollers |
| B | SNR | Tapered roller bearings | Design | Steeper angle serie |
| B | SNR | Ball bearings | Design | One row angular contact ball bearings : 40° contact angle Double row angular contact ball bearings : Steel cage ; 32° contact angle ; with filling slot |
| B | SNR | Ball bearings | Design | One row angular contact ball bearings : 40° contact angle Double row angular contact ball bearings : Steel cage ; 32° contact angle ; with filling slot |
| B | NTN | Ball bearings | Design | 40° contact angle |
| BG | SNR | Ball bearings | Design | 40° contact angle, universal design |
| BG | NTN | Ball bearings | Design | 40° contact angle, universal design |
| Bn | SNR | Bearing units | Others | Non-standard bearing insert with various features |
| C | NTN | Tapered roller bearings | Design | Steeper angle for 323xx serie (for metric items only) |
| C | SNR | Tapered roller bearings | Dimension | Conform to ISO |
| C | NTN | High precision angular contact ball bearings | Design | Contact angle 15° |
| C | SNR | High precision angular contact ball bearings | Design | Contact angle 15° |
| C | NTN | Needle roller bearings | Design | Special thread for European interchangeability (cam followers) |
| -C | NTN | Bearing units | Design | ntn-bearing_units-design--c-description to translate |
| C2 | NTN & SNR | Spherical roller bearings | Design | Internal radial clearance smaller than standard Cn clearance |
| C2 | SNR | Ball bearings | Design | Radial internal clearance, C2 class |
| C2 | NTN | Cylindrical roller bearings | Design | Radial internal clearance, C2 class |
| C2 | NTN | Bearing units | Design | Clearance < Normal |
| C2 | NTN | Ball bearings | Design | Radial internal clearance, C2 class |
| C3 | NTN & SNR | Spherical roller bearings | Design | Internal radial clearance higher than standard Cn clearance |
| C3 | SNR | Ball bearings | Design | Radial internal clearance, C3 class |
| C3 | NTN | Cylindrical roller bearings | Design | Radial internal clearance, C3 class |
| C3 | NTN | Bearing units | Design | Clearance > Normal |
| C3 | NTN | Ball bearings | Design | Radial internal clearance, C3 class |
| C4 | NTN & SNR | Spherical roller bearings | Design | Internal radial clearance higher than C3 |
| C4 | SNR | Ball bearings | Design | Radial internal clearance, C4 class |
| C4 | NTN | Cylindrical roller bearings | Design | Radial internal clearance, C4 class |
| C4 | NTN | Bearing units | Design | Clearance > C3 ("C4" is standard for "HT2" type so not shown) |
| C4 | NTN | Ball bearings | Design | Radial internal clearance, C4 class |
| C5 | NTN & SNR | Spherical roller bearings | Design | Internal radial clearance higher than C4 |
| C5 | SNR | Ball bearings | Design | Radial internal clearance, C5 class |
| C5 | NTN | Cylindrical roller bearings | Design | Radial internal clearance, C5 class |
| C5 | NTN | Bearing units | Design | Clearance > C4 |
| C5 | NTN | Ball bearings | Design | Radial internal clearance, C5 class |
| CC | SNR | Bearing units | Component | Bearing unit with narrow steel cover (closed version) |
| CCE | SNR | Bearing units | Component | Bearing unit with wide steel cover (closed version) |
| CM | NTN | Ball bearings | Design | Special normal radial internal clearance with tighten tolerances |
| CN | NTN | Bearing units | Design | Normal (bearing unit standard clearance) |
| CO | SNR | Bearing units | Component | Bearing unit with narrow plate cover for metric shaft (open version) |
| COE | SNR | Bearing units | Component | Bearing unit with wide steel cover for metric shaft (open version) |
| COEU | SNR | Bearing units | Component | Bearing unit with wide steel cover for imperial shaft (open version) |
| COU | SNR | Bearing units | Component | Bearing unit with narrow steel cover for imperial shaft (open version) |
| CSnn-n | NTN | Ball bearings | Design | Special clearance |
| CT | NTN | Needle roller bearings | Others | Welded cage + special heat treament on outer ring to increase lifespan |
| CT1 | NTN | Bearing units | Others | Bearing insert for operating temperature up to -60°C |
| D | NTN | Tapered roller bearings | Design | Steeper angle serie (313xx = 303xxD) (for metric items only) |
| D | NTN | Needle roller bearings | Design | Lubrication hole |
| D0 | NTN | Needle roller bearings | Design | No lubrication hole (cam followers) |
| D1 | NTN | Tapered roller bearings | Design | Lubrication holes & groove |
| D1 | NTN | Spherical roller bearings | Design | Lubrication groove and lubrication holes on outer ring |
| D1 | NTN | Bearing units | Component | Relubricatable type |
| D1 | NTN | Needle roller bearings | Design | Lubrication hole + lubrication groove |
| D2 | NTN | Bearing units | Component | Relubricatable type with anti-rotation ball. Outer diameter with minus tolerance |
| D3 | NTN | Bearing units | Component | Relubricatable type with anti-rotation ball. Outer diameter with normal tolerance |
| DB | NTN | Tapered roller bearings | Assembly | Face to face paired bearings |
| DB | SNR | Tapered roller bearings | Assembly | Back to back arrangement |
| DB | NTN & SNR | High precision angular contact ball bearings | Assembly | O layout |
| DC | NTN | Tapered roller bearings | Assembly | Double cup with one hole counter-bored for lockin pin |
| DF | NTN | Tapered roller bearings | Assembly | Face to face arrangement |
| DF | SNR | Tapered roller bearings | Assembly | Face to face arrangement |
| DF | NTN & SNR | High precision angular contact ball bearings | Assembly | X layout |
| DT | NTN | Tapered roller bearings | Assembly | Tandem arrangement |
| DT | NTN & SNR | High precision angular contact ball bearings | Assembly | Tandem layout |
| DU | NTN | Tapered roller bearings | Design | D for steeper angle serie (313xx = 303xxD), U for through hardening steel (for metric items only) |
| DU TU QU | SNR | High precision angular contact ball bearings | Assembly | Sets of 2, 3, 4 universal bearings |
| Dxxx | SNR | Ball bearings | Component | Grease type if non standard |
| E | SNR | Ball bearings | Component | Contact seal on one side |
| E1 | NTN | Tapered roller bearings | Design | Cut crowning profile (for metric items only) |
| EA | NTN & SNR | Spherical roller bearings | Component | Ultage design, steel cage |
| EA | NTN | Cylindrical roller bearings | Design | Ultage design |
| EE | SNR | Spherical roller bearings | Component | Sealed (2 NBR seals) |
| EE | SNR | Ball bearings | Component | Contact seals on both sides |
| EE3 | SNR | Spherical roller bearings | Component | Sealed (2 FKM seals) |
| EE4 | SNR | Spherical roller bearings | Component | Sealed (2 HNBR seals) |
| EG15 | SNR | Spherical roller bearings | Component | Ultage design, glass-fiber reinforced polyamide cage |
| -EL | NTN | Bearing units | Design | No eccentric locking collar for eccentric locking collar type |
| EM | NTN & SNR | Spherical roller bearings | Component | Ultage design, massive brass cage |
| EMTR | SNR | Ball bearings | Others | Electric motor product range |
| EW | NTN | Tapered roller bearings | Design | Optimized profile for raceways |
| F | NTN | Needle roller bearings | Component | Special strengthened cage (Cam and Roller Followers) |
| F1 | NTN | Ball bearings | Component | Machined carbon steel cage |
| F1 | NTN | Needle roller bearings | Component | Machined steel cage |
| F2 | NTN | Ball bearings | Component | Machined stainless steel cage |
| F600 | SNR | Ball bearings | Others | TOPLINE range for very high temperature - Maximum 350°C, 50 rpm - Open bearing with surface treatment |
| F604 | SNR | Ball bearings | Others | TOPLINE range for very high temperature - Maximum 350°C, 50 rpm - Shielded bearing with grease |
| F605 | SNR | Ball bearings | Others | TOPLINE range for very high temperature - Maximum 350°C, 50 rpm - Open bearing |
| F800 | SNR | Spherical roller bearings | Others | Bearing with massive brass cage for vibrating applications, special C4 clearance |
| F801 | SNR | Spherical roller bearings | Others | Bearing with massive brass cage for vibrating applications, special C3 clearance |
| F802 | SNR | Spherical roller bearings | Others | Bearing with massive brass cage for vibrating applications, special CN clearance |
| FD | SNR | Bearing units | Others | Bearing insert for food industry |
| FG1 | SNR | Bearing units | Others | Bearing insert for food industry |
| FM | NTN | Needle roller bearings | Material | Special heat treatment on outer ring to increase lifespan |
| FT150 | SNR | Ball bearings | Others | TOPLINE range for high temperature - Maximum 150°C with FKM seals on both sides |
| FT150ZZ | SNR | Ball bearings | Others | TOPLINE range for high temperature - Maximum 150°C with shields on both sides |
| G | NTN | High precision angular contact ball bearings | Assembly | Universal bearing |
| G1 | NTN | Cylindrical roller bearings | Component | Massive brass cage |
| G14 | SNR | Ball bearings | Component | Polyamide 6.6 cage |
| G15 | SNR | Ball bearings | Component | Polyamide 6.6 cage with glass fibers |
| G15 | SNR | Cylindrical roller bearings | Component | Polyamide cage |
| G2 | SNR | Bearing units | Component | SNR 2 line regreasing system with 4 bores in the OR |
| GD2 GD3 GD4 | NTN | High precision angular contact ball bearings | Assembly | Sets of 2, 3, 4 universal bearings |
| GL GN GM GH | NTN | High precision angular contact ball bearings | Design | Preloads (Light, Normal, Medium, Heavy) |
| H | SNR | High precision angular contact ball bearings | Design | Contact angle 25° |
| H | NTN | Needle roller bearings | Design | Hexagonal socket (cam followers) |
| H | SNR | Bearing units | Design | UK bearing insert equipped with adapter sleeve |
| H7 | SNR | Bearing units | Design | Special tolerance of spherical bearing seat: H7 |
| HT2 | NTN | Bearing units | Others | Bearing insert for operating temperature up to +180°C |
| HT200 | SNR | Ball bearings | Others | TOPLINE range for high temperature - Maximum 200°C with FKM seals on both sides |
| HT200ZZ | SNR | Ball bearings | Others | TOPLINE range for high temperature - Maximum 200°C with shields on both sides |
| HVZZ | SNR | Ball bearings | Others | TOPLINE range- High speed bearings with shields on both sides |
| I | SNR | Bearing units | Dimension | Thermoplastic housing TBL with mounting bores (imperial) |
| J | NTN | Tapered roller bearings | Component | Steel cage |
| J | NTN | Cylindrical roller bearings | Component | Pressed steel cage |
| J | NTN | Ball bearings | Component | Pressed steel cage |
| J, JW | NTN | Needle roller bearings | Component | Special stamped steel cage |
| J30 | SNR | Cylindrical roller bearings | Design | = C3 clearance |
| J40 | SNR | Cylindrical roller bearings | Design | = C4 clearance |
| J74, J84, J94 | SNR | High precision angular contact ball bearings | Design | Preloads (Light, Medium, Heavy) for standard range |
| J74S, J84S, J94S | SNR | High precision angular contact ball bearings | Design | Preloads (Light, Medium, Heavy) for high speed range |
| JR | NTN | Ball bearings | Component | Bearing with pressed rivet cage |
| JR2 | NTN | Ball bearings | Component | Cage with reinforced type of pressed steel |
| K | NTN & SNR | Spherical roller bearings | Design | Tapered bore, taper 1:12 |
| K | SNR | Ball bearings | Design | Tapered bore, taper 1:12 |
| K | NTN | Ball bearings | Design | Tapered bore (1:12) |
| K30 | NTN & SNR | Spherical roller bearings | Design | Tapered bore, taper 1:30 |
| L | NTN | Tapered roller bearings | Design | Seal feature on cone |
| L | SNR | Spherical roller bearings | Others | Low Noise |
| L | NTN | Needle roller bearings | Component | One Seal |
| L | NTN | Bearing units | Design | Cylindrical outer ring width: matching to JIS |
| L1 | NTN | Spherical roller bearings | Component | Massive brass cage |
| L1 | NTN | Ball bearings | Component | Machined brass cage |
| L1 | NTN | Needle roller bearings | Component | Brass cage |
| L1B | NTN | Ball bearings | Component | Machined brass cage centered on balls |
| L3 | NTN | Needle roller bearings | Component | Aluminium cage |
| L3 | SNR | Bearing units | Component | Bearing insert with triple lip seal |
| L4 | SNR | Bearing units | Component | Bearing insert with multiple seal and reduced rotation torque |
| LB, LLB | NTN | Ball bearings | Component | Nitrile non-friction seal |
| LB, LLB | NTN | Bearing units | Component | Non-contact seal (LB: one side, LLB: both sides) |
| LH, LLH | NTN | Ball bearings | Component | Nitrile low torque seal |
| LJ, LLJ | NTN | Bearing units | Component | Triple lip seal (LJ: one side, LLJ: both sides) |
| LL | NTN | Needle roller bearings | Component | Two seals |
| LLB | NTN | High precision angular contact ball bearings | Component | Nitrile non-friction seal (-25 to +120°C) |
| LLS | NTN | Spherical roller bearings | Component | Sealed (2 NBR seals) |
| LP | SNR | Bearing units | Design | Bearing insert with anti rotation pin (opposite side of shaft fixation) |
| LP03 | NTN | Ball bearings | Component | Standard solid grease |
| LP09 | NTN | Ball bearings | Component | Food solid grease |
| LPE | SNR | Bearing units | Design | Bearing insert with anti rotation pin (on side of shaft fixation) |
| LS, LLS | NTN | Bearing units | Component | High torque triple lip seal (LS:one side, LLS:both sides) |
| LT | SNR | Ball bearings | Others | TOPLINE range for Low Temperature - Minimum -40°C with seals on both sides |
| LTZZ | SNR | Ball bearings | Others | TOPLINE range for Low Temperature - Minimum -60°C with shields on both sides |
| LU, LLU | NTN | Ball bearings | Component | Nitrile double lip contact seal |
| LU, LLU | NTN | Bearing units | Component | Contact seal (LU:one side, LLU:both sides) |
| M | SNR | Ball bearings | Component | Massive brass cage, centered on balls |
| MA | SNR | Ball bearings | Component | Massive brass cage, centered on outer ring |
| MB | SNR | Ball bearings | Component | Massive brass cage, centered on inner ring |
| Mn | SNR | Bearing units | Design | Cast housings with metric mounting thread (size) instead of through bore |
| N | SNR | Spherical roller bearings | Design | Groove for snap ring on outer ring |
| N | SNR | Ball bearings | Design | Groove on outer ring |
| N | SNR | Bearing units | Design | Housing designed for steel cover installation (grooves) |
| N | NTN | Bearing units | Material | Material SC460(JIS) |
| N | NTN | Bearing units | Design | Bearing insert with snap ring groove |
| N | NTN | Ball bearings | Design | Groove on outer ring |
| N1 | SNR | Spherical roller bearings | Design | Anti rotation slot on outer ring |
| N1 | NTN | Bearing units | Material | Material FCD450(JIS) |
| N2 | SNR | Ball bearings | Design | Two snap rings on outer ring |
| NR | SNR | Ball bearings | Design | Groove and snap ring on outer ring |
| NR | NTN | Bearing units | Design | Bearing insert with snap ring groove and snap ring |
| NR | NTN | Ball bearings | Design | Groove and snap ring on outer ring |
| NRS | NTN | Bearing units | Design | Bearing insert with snap ring groove and snap ring on opposite side of standard |
| NS | NTN | Bearing units | Design | Bearing insert with snap ring groove on opposite side of standard |
| NX | NTN | Bearing units | Material | Material SS400(JIS) |
| P* | SNR | Tapered roller bearings | Design | Precision class |
| P* | NTN | Cylindrical roller bearings | Design | Precision class |
| P2 | NTN | Tapered roller bearings | Design | Tolerance class 2 |
| P2 | SNR | Tapered roller bearings | Design | Tolerance class 2 |
| P2 | SNR | Ball bearings | Design | P2 precision class |
| P2 | NTN | Cylindrical roller bearings | Design | Tolerance class 2 |
| P2 | NTN | Ball bearings | Design | P2 precision class |
| P4 | NTN | Tapered roller bearings | Design | Tolerance class 4 |
| P4 | NTN | Tapered roller bearings | Design | Tolerance class 4 |
| P4 | NTN | Ball bearings | Design | P4 precision class |
| P4 | NTN | High precision angular contact ball bearings | Design | Precision class JIS 4/ ISO 4 |
| P4 | NTN | Cylindrical roller bearings | Design | Tolerance class 4 |
| P4 | SNR | Ball bearings | Design | P4 precision class |
| P42 | NTN | High precision angular contact ball bearings | Design | Precision class JIS 4 for the dimensions and JIS 2 for the run out in rotation |
| P5 | NTN | Tapered roller bearings | Design | Tolerance class 5 |
| P5 | SNR | Tapered roller bearings | Design | Tolerance class 5 |
| P5 | SNR | Ball bearings | Design | P5 precision class |
| P5 | NTN | Cylindrical roller bearings | Design | Tolerance class 5 |
| P5 | NTN | Ball bearings | Design | P5 precision class |
| P6 | NTN | Tapered roller bearings | Design | Tolerance class 6 |
| P6 | SNR | Ball bearings | Design | P6 precision class |
| P6 | NTN | Ball bearings | Design | P6 precision class |
| P63E | NTN | Ball bearings | Design | P6 precision class + C3 internal clearance + electric motor quality |
| P6X | NTN | Tapered roller bearings | Design | Tolerance class 6X |
| P6X | SNR | Tapered roller bearings | Design | Tolerance class 6X |
| P6X | NTN | Cylindrical roller bearings | Design | 6X precision tolerance class |
| PK | NTN | Tapered roller bearings | Design | Tolerance class K (ABMA, J series) (for inch items only) |
| PX1, PX2, ...PXn | NTN | Tapered roller bearings | Design | Special tolerance |
| QT | NTN | Ball bearings | Component | More than 50% grease filling rate |
| QT70 | SNR | Spherical roller bearings | Component | Bearing volume filled with 70% of grease |
| R | NTN | Tapered roller bearings | Assembly | Cone not be interchanged with other cup |
| S | NTN | Tapered roller bearings | Dimension | Outside dimensions modification (for inch items only) |
| S | SNR | Ball bearings | Design | Spherical outer diameter |
| S | NTN | Needle roller bearings | Component | Welded steel cage |
| -S | NTN | Bearing units | Design | Housing designed for steel cover installation (grooves) |
| SA | NTN | Tapered roller bearings | Assembly | Specification for quick assembly of the bearing |
| SGn | SNR | Bearing units | Component | Bearing insert filled with special grease |
| SRS | SNR | Bearing units | Others | Bearing insert for rubber damping ring use |
| ST | NTN | Tapered roller bearings | Design | Low torque specification |
| T04 | SNR | Bearing units | Others | Bearing insert for operating temp up to -40°C |
| T1 | NTN | High precision angular contact ball bearings | Component | Phenolic machined cage |
| T2 | NTN | High precision angular contact ball bearings | Component | Plastic, nylon or Teflon cage |
| T2 | NTN | Cylindrical roller bearings | Component | Polyamide cage PA66 + GF |
| T2 | NTN | Ball bearings | Component | Polyamide resin molded cage |
| T2 | NTN | Needle roller bearings | Component | Polyamide cage |
| T20 | SNR | Bearing units | Others | Bearing insert for operating temp up to +200°C |
| T2X | NTN | Cylindrical roller bearings | Component | Polyamide cage PA46 + GF |
| T2X | NTN | Ball bearings | Component | Polyamide 6.6 + Glass fiber 25% |
| TD | NTN | Tapered roller bearings | Design | Cone with tapered bore |
| U | NTN | Tapered roller bearings | Material | Through hardening steel SUJ2 & interchangeability (for metric items only) |
| U | SNR | High precision angular contact ball bearings | Assembly | Universal bearing |
| U | NTN | Ball bearings | Component | Open bearing with existing groove to put seal afterwards |
| U | NTN | Bearing units | Component | Non-contact shield ("U" is standard for "HT2" and "CT1" types so not shown) |
| U1 | NTN | Bearing units | Component | Non-contact seal |
| U2 | NTN | Bearing units | Component | Non-contact stainless shield |
| UA | NTN | Spherical roller bearings | Component | Ultage design, massive brass cage centered on outer ring for vibrating applications |
| UP | NTN | High precision angular contact ball bearings | Design | Ultra precision |
| UTG | NTN | Tapered roller bearings | Design | Ultage design |
| V1, V2, ...Vn | NTN | Tapered roller bearings | Design | Particular specification |
| W | SNR | Bearing units | Design | Thermoplastic housing without grease bore |
| W, W-1 | NTN | Ball bearings | Design | Raceway with slot or knock hole or/and tapping hole |
| W2 | NTN | Bearing units | Component | Bearing insert with knurled cup point set screws |
| W3 | NTN | Bearing units | Component | Bearing insert with cup point set screws |
| W33 | SNR | Spherical roller bearings | Design | Lubrication groove and lubrication holes on outer ring |
| W34 | SNR | Spherical roller bearings | Design | Lubrication holes on outer ring (no lubrication groove) |
| W4 | NTN | Bearing units | Component | Bearing insert with double point set screws |
| W5, W55 | NTN | Bearing units | Component | Bearing insert with dog point set screws (W5: 1 piece, W55: 2 pieces) |
| W6, W66 | NTN | Bearing units | Component | Bearing insert with key bolt set screws (W6: 1 piece, W66: 2 pieces) |
| W7-n | NTN | Bearing units | Component | Bearing insert with special set screws (2 pieces) |
| W8 | NTN | Bearing units | Design | Bearing insert with American Standard (ANSI) unified thread system (2 pieces) |
| X | NTN | Tapered roller bearings | Design | Width of cone B = total width T (for metric items only) |
| X1, X2, …Xn | NTN | Tapered roller bearings | Design | Special corner radii (n = number) |
| X1, X2, Xn… | NTN | Ball bearings | Design | Chamfer modification |
| X1, X2, Xn… | NTN | Needle roller bearings | Design | Chamfer modification |
| XU | NTN | Tapered roller bearings | Material | X + Through Hardened Steel + interchangeability (for metric items only) |
| Y | NTN | Ball bearings | Component | Pressed brass cage |
| Y | SNR | Bearing units | Material | Design optimized cast housings with standard dimensions and zinc plating |
| Z | SNR | Ball bearings | Component | Shield on one side |
| Z | NTN | Needle roller bearings | Component | One shield |
| Z, ZZ | NTN | Ball bearings | Component | Steel shield |
| Z1, ZZ1 | NTN | Ball bearings | Component | Stainless steel shield |
| ZW | NTN | Needle roller bearings | Component | Two row cage |
| ZZ | SNR | Ball bearings | Component | Shields on both sides |
| ZZ | NTN | Needle roller bearings | Component | Shields on both sides |
