The Bearing,sleeve, cataloged under National Stock Number 3120-01-259-9571, is classified within Federal Supply Class 3120 (Bearings, Plain, Unmounted) of the Bearings group. The manufacturer of record is New Hampshire Ball Bearings Inc Div Astro Division. Government technical data includes 3 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 3120-01-259-9571 |
| Primary Part Number | B365-4-021 |
| Item Name | Bearing,sleeve |
| FSC / FSG | 3120 / 31 — Bearings, Plain, Unmounted |
| Manufacturer | New Hampshire Ball Bearings Inc Div Astro Division |
| Status | ACTIVE |
| Body Outside Diameter | 0.3115 INCHES MINIMUM AND 0.3120 INCHES MAXIMUM IN |
| Body Inside Diameter | 0.2500 INCHES MINIMUM AND 0.2515 INCHES MAXIMUM IN |
| Material | STEEL COMP 630 OR STEEL COMP 321 OVERALL |
| 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 |
|---|---|
| B365-4-021 PRIMARY | New Hampshire Ball Bearings Inc Div Astro Division (USA) |
| H-4-021 PRIMARY | Roller Bearing Company of America, Inc. (USA) |
| Reference | Meaning |
|---|---|
| GL519A4-021 | 7/2 Vendor item drawing reference Northrop Grumman Systems Corporation |
NSN 3120-01-259-9571 is a Bearing,sleeve, manufactured by New Hampshire Ball Bearings Inc Div Astro Division, classified under FSC 3120, Bearings, Plain, Unmounted. Status: active.
NSN 3120-01-259-9571 has 2 manufacturer part numbers on file: B365-4-021 (New Hampshire Ball Bearings Inc Div Astro Division), H-4-021 (Roller Bearing Company of America, Inc.).
1 possible match (shared part number, not a government interchangeability claim): 5998-01-407-3356. Verify interchangeability with system specifications before substitution.
Key specifications for B365-4-021: Body Outside Diameter: 0.3115 INCHES MINIMUM AND 0.3120 INCHES MAXIMUM IN; Overall Length: 0.2050 INCHES MINIMUM AND 0.2100 INCHES MAXIMUM IN; Body Inside Diameter: 0.2500 INCHES MINIMUM AND 0.2515 INCHES MAXIMUM IN; Material: STEEL COMP 630 OR STEEL COMP 321 OVERALL. 3 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.