The O-Ring, cataloged under National Stock Number 5331-01-682-9571, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division. Government technical data includes 4 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. 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 | 5331-01-682-9571 |
| Primary Part Number | 5-256NBR |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division |
| Status | ACTIVE |
| Hardness Rating | 90.0 SHORE DUROMETER A NOMINAL |
| Nondefinitive Spec/std Data | 2.62MM WIDTH MM |
| Center Hole Diameter | 17.96 MILLIMETERS NOMINAL MM |
| 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 |
|---|---|
| 5-256NBR PRIMARY | Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division (USA) |
NSN 5331-01-682-9571 is a O-Ring, manufactured by Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division, classified under FSC 5331, O-ring. Status: active.
NSN 5331-01-682-9571 has 1 manufacturer part number on file: 5-256NBR (Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division).
1 possible match (shared part number, not a government interchangeability claim): 5331-01-727-6023. Verify interchangeability with system specifications before substitution.
Key specifications for 5-256NBR: Hardness Rating: 90.0 SHORE DUROMETER A NOMINAL; Nondefinitive Spec/std Data: 2.62MM WIDTH MM; Center Hole Diameter: 17.96 MILLIMETERS NOMINAL MM; Part Name Assigned by Controlling Agency: O-RING 1/2 INCH-14 IN. 4 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.