The O-Ring, cataloged under National Stock Number 5331-01-721-5256, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc. 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | O-Ring |
| FSC / FSG | 5331 — O-ring (FSG 53) |
| Manufacturers | Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc (CAGE 76364) |
| Parameter | Value |
|---|---|
| NSN | 5331-01-721-5256 |
| Primary Part Number | 65154-022-922 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc |
| Status | ACTIVE |
| 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 |
|---|---|
| 65154-022-922 PRIMARY | Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc (USA) |
| Reference | Meaning |
|---|---|
| 161B-A56J 12 | D/9 Drawing number reference only Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc |
| 161B-A56J 12 REV A ITEM 20 | C/1 Advisory reference — outside the item-of-supply concept Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc |
NSN 5331-01-721-5256 is a O-Ring, manufactured by Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc, classified under FSC 5331, O-ring. Status: active.
NSN 5331-01-721-5256 has 1 manufacturer part number on file: 65154-022-922 (Milwaukee Valve Co, Inc Div Milwaukee Valve Company, Llc).
3 possible matches (shared part number, not a government interchangeability claim): 4820-01-722-4579, 4820-01-722-5535, 4820-01-722-5542. Verify interchangeability with system specifications before substitution.
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.