The O-Ring, cataloged under National Stock Number 5331-00-633-6819, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Prestolite Electric Inc. Government technical data includes 3 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5331-00-633-6819 |
| Primary Part Number | 74978 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Prestolite Electric Inc |
| Status | ACTIVE |
| Cross-Sectional Height | 0.100 INCHES MINIMUM AND 0.106 INCHES MAXIMUM IN |
| Center Hole Diameter | 1.852 INCHES MINIMUM AND 1.872 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 | X |
| Part Number | Manufacturer |
|---|---|
| 74978 PRIMARY | Prestolite Electric Inc (USA) |
| Reference | Meaning |
|---|---|
| 74978 | 5/9 Secondary reference Prestolite Electric Inc |
| Z053074978 | 5/9 Secondary reference Prestolite Electric Inc |
NSN 5331-00-633-6819 is a O-Ring, manufactured by Prestolite Electric Inc, classified under FSC 5331, O-ring. Status: active.
NSN 5331-00-633-6819 has 1 manufacturer part number on file: 74978 (Prestolite Electric Inc).
1 possible match (shared part number, not a government interchangeability claim): 5340-01-657-0220. Verify interchangeability with system specifications before substitution.
Key specifications for 74978: Cross-Sectional Height: 0.100 INCHES MINIMUM AND 0.106 INCHES MAXIMUM IN; Center Hole Diameter: 1.852 INCHES MINIMUM AND 1.872 INCHES MAXIMUM IN; Material: RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR. 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.