The O-Ring, cataloged under National Stock Number 5331-01-278-3946, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. Government technical data includes 8 specifications, cited from the U.S. Government catalog. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5331-01-278-3946 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Status | ACTIVE |
| Temp Rating | -65.0 FAHRENHEIT AND 275.0 FAHRENHEIT DEGF |
| Cross-Sectional Height | 0.135 INCHES MINIMUM AND 0.143 INCHES MAXIMUM IN |
| Criticality Code Justification | ZZZW |
| Elongation Percentage | 160 MAXIMUM |
| Departure From Cited Document | MATERIAL WILL BE IN ACCORDANCE WITH SHIPS PARTS CONTROL CENTER ACTIVITY HX QUALITY CONTROL,MANUFACTURING AND TESTING SPECIFICATIONS |
| Peripheral Diameter | 4.137 INCHES NOMINAL IN |
| Center Hole Diameter | 3.844 INCHES MINIMUM AND 3.874 INCHES MAXIMUM IN |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | Y |
| Reference | Meaning |
|---|---|
| SAE-AS28775 | 3/1 Design control — primary reference Sae International Dba Sae International |
| MS28775-241 | 5/9 Secondary reference U.S. Government activity |
| MS28775-241 | 5/9 Secondary reference U.S. Government activity |
| MS28775-241 | 3/1 Design control — primary reference Sae International Dba Sae International |
| 8-400631PC13 | 5/9 Secondary reference National Oilwell |
NSN 5331-01-278-3946 is a O-Ring, classified under FSC 5331, O-ring. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5331-01-279-0945. Verify interchangeability with system specifications before substitution.
Key specifications for 5331-01-278-3946: Temp Rating: -65.0 FAHRENHEIT AND 275.0 FAHRENHEIT DEGF; Cross-Sectional Height: 0.135 INCHES MINIMUM AND 0.143 INCHES MAXIMUM IN; Criticality Code Justification: ZZZW; Elongation Percentage: 160 MAXIMUM. 8 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.