MPNbase

12×37×12 mm bearings

25 models from 4 brands across 3 types share this ISO 15 envelope: 12 mm bore, 37 mm outside diameter, 12 mm width (0.472×1.457×0.472 in), 12.5 mm radial section.

25 models fit this space 4 brands 25 with catalogue C rating

Dimensional interchange — verify before substituting

These bearings are interchangeable on boundary dimensions per ISO 15 — same bore, OD and width. They are not guaranteed drop-in equivalents: compare load ratings, seals, clearance, cage, precision and axial-locating design for the specific duty. Models without a catalogue C rating on this site carry ISO 15 geometry only; request the manufacturer table before a load-critical replacement.

Model Type Brand Seal Clearance C (kN) C0 (kN) Mass (g)
1301 Self-Aligning Ball NTN open — 9.65 2.16 68
1301-ETN9 Self-Aligning Ball SKF open CN 9.36 2.16 67
6301 Deep Groove Ball SKF open CN 10.1 4.15 60
6301-2RS Deep Groove Ball SKF 2RS CN 10.1 4.15 62
6301-2RS-FAG Deep Groove Ball FAG 2RS CN 11.5 4.2 59
6301-2RS-NSK Deep Groove Ball NSK 2RS CN 10.7 4.2 60
6301-2RS-NTN Deep Groove Ball NTN 2RS CN 10.8 4.2 60
6301-FAG Deep Groove Ball FAG open CN 11.5 4.2 62
6301-NSK Deep Groove Ball NSK open CN 10.7 4.2 60
6301-NTN Deep Groove Ball NTN open CN 10.8 4.2 60
6301-RSR Deep Groove Ball SKF RSR CN 10.1 4.15 60
6301-RSR-NSK Deep Groove Ball NSK RSR CN 10.7 4.2 60
6301-RSR-NTN Deep Groove Ball NTN RSR CN 10.8 4.2 60
6301-ZZ Deep Groove Ball SKF ZZ CN 10.1 4.15 63
6301-ZZ-FAG Deep Groove Ball FAG ZZ CN 11.5 4.2 59
6301-ZZ-NSK Deep Groove Ball NSK ZZ CN 10.7 4.2 60
6301-ZZ-NTN Deep Groove Ball NTN ZZ CN 10.8 4.2 60
7301 Angular Contact Ball SKF open CN 10.6 5 60
7301-BE-2RZP Angular Contact Ball SKF RSR CN 10.6 5 60
7301-BEP Angular Contact Ball SKF open CN 10.6 5 60
7301-NTN Angular Contact Ball NTN open CN 12.4 5.25 44
7301B Angular Contact Ball NTN open CN 11.7 4.95 45
W6301 Deep Groove Ball SKF open CN 8.32 4.15 56
W6301-2RS Deep Groove Ball SKF 2RS CN 8.32 4.15 58
W6301-ZZ Deep Groove Ball SKF ZZ CN 8.32 4.15 60

Note: catalogue dynamic load ratings for this envelope span 8.3– 12.4 kN — a 49% spread between designs in the very same 12×37×12 mm space. The higher-rated unit is not an upgrade for every duty (it may run at lower limiting speed), but ignoring the gap will over- or under-life the replacement.

Substitution verification checklist

  1. Load rating. Check C (dynamic) and C0 (static) against the original life calculation — the table above shows which models carry verified catalogue values.
  2. Sealing. Open, -ZZ shields and -2RS contact seals are not equivalent in friction, speed or contamination protection; match the housing environment, not just the suffix on the old box.
  3. Internal clearance. CN/C3/C4 changes with fit and operating temperature; an interference inner-ring mount commonly needs C3 where the bench bearing ran CN.
  4. Cage and precision. Stamped steel, machined brass and polymer cages, and P0/P6/P5 tolerance classes, carry different speed and shock limits.
  5. Locating behaviour. Within one envelope an NU cylindrical roller floats axially while an NJ/NUP locates; ball designs take thrust that roller locating schemes do not. Preserve the shaft's locating arrangement.

Browse all 12 mm bore bearings for wider or narrower sections, or open a model page for naming-rule decode, applications and graded cross references: 1301, 1301-ETN9, 6301, 6301-2RS, 6301-2RS-FAG, 6301-2RS-NSK, 6301-2RS-NTN, 6301-FAG, 6301-NSK, 6301-NTN, 6301-RSR, 6301-RSR-NSK, 6301-RSR-NTN, 6301-ZZ, 6301-ZZ-FAG, 6301-ZZ-NSK, 6301-ZZ-NTN, 7301, 7301-BE-2RZP, 7301-BEP, 7301-NTN, 7301B, W6301, W6301-2RS, W6301-ZZ.

Frequently asked questions

Are all 12×37×12 mm bearings interchangeable?

They share the same ISO 15 boundary dimensions — 12 mm bore, 37 mm OD, 12 mm width (0.472×1.457×0.472 in) — so they fit the same shaft, housing bore and axial space. Interchangeability ends at the envelope: dynamic load rating, seal arrangement, internal clearance, cage and precision class differ between the 25 models listed here and must be checked against the duty before substitution.

Is it a drop-in replacement if two bearings both measure 12×37×12?

Only after verification. Confirm five things in order: (1) the C/C0 load ratings meet the original life calculation, (2) the seal type is equivalent or acceptable for the contamination level (open vs -ZZ vs -2RS), (3) internal clearance matches (CN/C3/C4 — an interference fit changes residual play), (4) cage material and precision class suit the speed, and (5) the axial-locating behaviour is the same (for example an NU cylindrical roller floats while an NJ locates one way). Same dimensions alone never guarantee equal performance.

What is 12×37×12 mm in inches?

12×37×12 mm converts to 0.472×1.457×0.472 in, with a 12.5 mm (0.492 in) radial section height. These are the ISO 15 general-plan envelope dimensions shared across manufacturers, which is why models such as 1301, 1301-ETN9, 6301 mount in the same space despite different internal designs.