The O-Ring, cataloged under National Stock Number 5331-00-536-9858, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Dressta North America Ltd. Government technical data includes 2 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5331-00-536-9858 |
| Primary Part Number | 21056R1 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Dressta North America Ltd |
| Status | ACTIVE |
| Cross-Sectional Height | 0.125 INCHES NOMINAL IN |
| Material | RUBBER SYNTHETIC |
| 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 |
|---|---|
| 21056R1 PRIMARY | Dressta North America Ltd (USA) |
| Reference | Meaning |
|---|---|
| 259099R1 | 5/9 Secondary reference U.S. Government activity |
| 21056R1 | 5/9 Secondary reference U.S. Government activity |
| 259099R1 | 5/9 Secondary reference Navistar International Corporation Dba Navistar |
NSN 5331-00-536-9858 is a O-Ring, manufactured by Dressta North America Ltd, classified under FSC 5331, O-ring. Status: active.
NSN 5331-00-536-9858 has 1 manufacturer part number on file: 21056R1 (Dressta North America Ltd).
2 possible matches (shared part number, not a government interchangeability claim): 5365-01-062-3857, 3110-01-502-7424. Verify interchangeability with system specifications before substitution.
Key specifications for 21056R1: Cross-Sectional Height: 0.125 INCHES NOMINAL IN; Material: RUBBER SYNTHETIC. 2 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.