The Bearing,plain,self-Aligning, cataloged under National Stock Number 3120-01-348-8580, is classified within Federal Supply Class 3120 (Bearings, Plain, Unmounted) of the Bearings group. The manufacturer of record is Sae International Dba Sae International. Government technical data includes 14 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3120-01-348-8580 |
| Primary Part Number | MS21155B7 |
| Item Name | Bearing,plain,self-Aligning |
| FSC / FSG | 3120 / 31 — Bearings, Plain, Unmounted |
| Manufacturer | Sae International Dba Sae International |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OUTER RACE MEMBER |
| Inner Member Width | 0.4350 INCHES MINIMUM AND 0.4370 INCHES MAXIMUM IN |
| Hardness Rating | 56.0 ROCKWELL C MINIMUM INNER MEMBER |
| Hardness Rating | 27.0 ROCKWELL C MINIMUM AND 36.0 ROCKWELL C MAXIMUM OUTER RACE MEMBER |
| Outer Member Width | 0.3380 INCHES MINIMUM AND 0.3480 INCHES MAXIMUM IN |
| Style Designator | WITHOUT INSERT OR LINER |
| Material Document and Classification | AMS 5630 ASSN STD SINGLE MATERIAL RESPONSE INNER MEMBER |
| Material Document and Classification | ASTM B124 ASSN STD ALL MATERIAL RESPONSES OR ASTM B150 ASSN STD ALL MATERIAL RESPONSES OR ASTM B283 ASSN STD 1ST MATERIAL RESPONSE OR AMS 4640 ASSN STD 2ND MATERIAL RESPONSE OUTER RACE MEMBER |
| Surface Treatment | CADMIUM OUTER RACE MEMBER |
| Surface Treatment | CHROMIUM INNER MEMBER |
| Bore Diameter | 0.4370 INCHES MINIMUM AND 0.4375 INCHES MAXIMUM IN |
| Material | STEEL COMP 440C INNER MEMBER |
| Material | COPPER ALLOY 642 OR COPPER ALLOY 630 OUTER RACE MEMBER |
| Outer Member Outside Diameter | 0.9057 INCHES MINIMUM AND 0.9062 INCHES MAXIMUM IN |
| 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 |
|---|---|
| MS21155B7 PRIMARY | Sae International Dba Sae International (USA) |
| Reference | Meaning |
|---|---|
| MS21155B7 | 3/9 Design control — primary reference U.S. Government activity |
| MS21155B7 | 5/9 Secondary reference U.S. Government activity |
NSN 3120-01-348-8580 is a Bearing,plain,self-Aligning, manufactured by Sae International Dba Sae International, classified under FSC 3120, Bearings, Plain, Unmounted. Status: active.
NSN 3120-01-348-8580 has 1 manufacturer part number on file: MS21155B7 (Sae International Dba Sae International).
Key specifications for MS21155B7: Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OUTER RACE MEMBER; Inner Member Width: 0.4350 INCHES MINIMUM AND 0.4370 INCHES MAXIMUM IN; Hardness Rating: 56.0 ROCKWELL C MINIMUM INNER MEMBER; Hardness Rating: 27.0 ROCKWELL C MINIMUM AND 36.0 ROCKWELL C MAXIMUM OUTER RACE MEMBER. 14 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.