61905-2RS bearing: complete specifications & equivalents
The 61905-2RS is a ISO 15 radial bearing sized 25 x 42 x 9 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 25 mm |
| Outer diameter D | 42 mm |
| Width B | 9 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 7.02 kN |
| Basic static load rating C0 | 4.3 kN |
| Fatigue load limit Pu | 0.193 kN |
| Limiting speed (mechanical) | 10000 rpm |
| Operating temperature | -30 to +110 °C |
| Mass | 45 g |
| Manufacturer designation | SKF 61905-2RS1 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-25 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 61900-series range
| Bore d | 0.984 in |
|---|---|
| Outer diameter D | 1.654 in |
| Width B | 0.354 in |
| ISO bore code | 05 |
| Radial section height (D−d)/2 | 8.5 mm |
| Smallest bore in 61900-series | 3 mm |
| Largest outer diameter in 61900-series | 1120 mm |
| Width range across 61900-series | 3–118 mm |
| Bore position in 61900-series (smallest first) | 13 of 63 |
| Bore above smallest 61900-series size | 22 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61905-2RS-FAG | FAG | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 61905-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant differs (2RS vs OPEN) — confirm sealing suits the duty. |
| 61905-ZZ-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant differs (2RS vs ZZ) — confirm sealing suits the duty. |
| 61905-2RS-NSK | NSK | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 61905-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant differs (2RS vs OPEN) — confirm sealing suits the duty. |
| 61905-RSR-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant differs (2RS vs RSR) — confirm sealing suits the duty. |
| 61905-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant differs (2RS vs ZZ) — confirm sealing suits the duty. |
| 61905-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61905-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61905-RSR-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant (2RS vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61905-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×42×9 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
| W61905-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 61905-2RS1 shares the 25×42×9 mm envelope but rates differently (7.02/4.3 kN vs 6.05/4.5 kN) — not a load-rating equivalent. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 61905-2RS model number is decoded
In the 61900-series (diameter series 9 of ISO 15) the last two digits encode the bore: 61905 carries bore code 05 = 25 mm. Outside diameter 42 mm and width 9 mm come from the ISO 15 boundary-dimensions general plan. Suffix -2RS denotes two contact-type elastomer seals over a lifetime grease fill; the sealing lips add drag compared with open or shielded versions. For normal-load mounting with a rotating inner ring on a 25 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. SKF's contact-seal catalogue number is 61905-2RS1 (older text: -2RS1), mapped here from the industry-neutral -2RS spelling.
Typical equipment & failure modes
Common applications
- packaging machinery
- space-constrained gearboxes
- clutch and transmission assemblies
- robotics and automation joints
Known failure patterns
- seal-lip hardening and loss of pre-grease in sustained high-temperature service
- grease-life expiry in the sealed-for-life cavity (no relubrication path)
- rolling-contact fatigue spalling after the rated L10 life is exceeded
- brinelling from static overload or hammering during mounting
Selection pitfalls — read before you substitute
- A 25 mm shaft for 61905 should be finished to Ra ≤ 1.6 µm with square seating faces; at this bore a scored or oval journal shows up directly as running noise and early raceway damage.
- The 619xx thin section at 25 mm bore (8.5 mm section height) cannot shrug off the misalignment a standard section tolerates; keep the housing bores round and aligned, or edge contact will spall the raceways early.
- Heat is the enemy of the sealed 61905-2RS: sustained running near the lip temperature limit hardens the rubber, after which grease escapes and dirt tracks in — watch the housing temperature in hot drives.
- Never wash a sealed 61905-2RS in solvent or press it home via the outer ring; solvent destroys the grease thickener and mounting force through the seal deforms the lip.
- Shaft and housing fillets must clear the bearing chamfer so the 9 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
- A 25 mm bore listing showing the right d/D/B but no standard or precision-class reference may be a loose-tolerance import; measure bore/OD spread before fitting it to a machined shaft.
- SKF catalogues the contact-sealed version as 61905-2RS1 (older printings may read -2RS1); it is shipped pre-greased and its 10000 r/min limiting speed is set by seal-lip drag and grease life versus the open bearing's 36000 r/min thermal reference speed.
- The 7.02/4.3 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 61905-2RS bearing?
A 61905-2RS deep-groove ball bearing has a 25 mm bore, 42 mm outer diameter and 9 mm width (0.984 × 1.654 × 0.354 in), per ISO 15 boundary dimensions. It is fitted with two contact rubber seals and is normally pre-greased.
What does the 2RS suffix on 61905-2RS mean?
2RS means two contact elastomer seals, one each side, usually over a lifetime grease fill. Sealing against dust and moisture is better than ZZ shields, but the lip drag lowers the speed and temperature ceiling.
How does the 61900 compare with other series at the same 25 mm bore?
619 is a thin section one step above 618: 42×9 mm with an 8.5 mm radial section at 25 mm bore; a 6205 on the same bore is substantially larger and more heavily rated.
Are 61905 bearings from different brands interchangeable?
For boundary dimensions, yes: every brand's 61905 uses the same ISO 15 envelope (25×42×9 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting. Seal suffixes also differ by brand (2RS, DDU, LLU, 2RSL and similar).
What is the SKF designation and catalogue data for 61905-2RS?
In the SKF Rolling Bearings catalogue this size is listed as 61905-2RS1 — two contact elastomer seals over a lifetime grease fill, 25×42×9 mm per ISO 15. Quoted values: C 7.02 kN, C0 4.3 kN, Pu 0.193 kN, limiting speed 10000 r/min, mass 45 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61905-2RS.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-25. Read our editorial & correction policy.