The Bearing,ball,duplex, cataloged under National Stock Number 3110-01-030-4939, is classified within Federal Supply Class 3110 (Bearings, Antifriction, Unmounted) of the Bearings group. The manufacturer of record is Mpb Corporation Dba Mpb Corp. Government technical data includes 18 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3110-01-030-4939 |
| Primary Part Number | 3TCRS14-21UDB1704 |
| Item Name | Bearing,ball,duplex |
| FSC / FSG | 3110 / 31 — Bearings, Antifriction, Unmounted |
| Manufacturer | Mpb Corporation Dba Mpb Corp |
| Status | ACTIVE |
| Retainer Fabrication Method | MACHINED |
| Bearing Preload Rating | 4.0 POUNDS NOMINAL LBS |
| Internal Clearance | 0.0003 INCHES MINIMUM RADIAL AND 0.0008 INCHES MAXIMUM RADIAL IN |
| Surface Finish | GROUND |
| Shield Quantity | 2 |
| Style Designator | COUNTERBORED OUTER RINGS, NON-SEPARABLE, BACK TO BACK MOUNTING |
| Material Document and Classification | UNABLE TO DECODE |
| Overall Outside Diameter | 1.3121 INCHES MINIMUM AND 1.3125 INCHES MAXIMUM IN |
| Load Direction | RADIAL |
| Standard Tolerance Designation | ABEC NO.7 |
| Bore Diameter | 0.8748 INCHES MINIMUM AND 0.8750 INCHES MAXIMUM IN |
| Material | STEEL COMP 440C INNER RING |
| Material | OIL LUBRICATION |
| Material | STEEL COMP 440C OUTER RING |
| Material | COTTON AND PLASTIC PHENOLIC RETAINER |
| Material | STEEL COMP 440C BALL |
| Material | STEEL CORROSION RESISTING SHIELD |
| Lubrication Material Document and Classification | MIL-L-6085 MIL SPEC SINGLE MATERIAL RESPONSE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 3TCRS14-21UDB1704 PRIMARY | Mpb Corporation Dba Mpb Corp (USA) |
| Reference | Meaning |
|---|---|
| 901815 | 7/2 Vendor item drawing reference U.S. Government activity |
| SR540PTC3-1-ABEC7 | 3/2 Design control — primary reference U.S. Government activity |
| AMVW540KDCRVDBFS171 | 5/9 Secondary reference Timken Co Div the Timken Company |
NSN 3110-01-030-4939 is a Bearing,ball,duplex, manufactured by Mpb Corporation Dba Mpb Corp, classified under FSC 3110, Bearings, Antifriction, Unmounted. Status: active.
NSN 3110-01-030-4939 has 1 manufacturer part number on file: 3TCRS14-21UDB1704 (Mpb Corporation Dba Mpb Corp).
1 possible match (shared part number, not a government interchangeability claim): 8140-01-437-7238. Verify interchangeability with system specifications before substitution.
Key specifications for 3TCRS14-21UDB1704: Retainer Fabrication Method: MACHINED; Bearing Preload Rating: 4.0 POUNDS NOMINAL LBS; Internal Clearance: 0.0003 INCHES MINIMUM RADIAL AND 0.0008 INCHES MAXIMUM RADIAL IN; Surface Finish: GROUND. 18 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.