The O-Ring, cataloged under National Stock Number 5331-01-540-4570, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Core Industries Inc. Dba Mueller Steam Specialty. Government technical data includes 1 specification, 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5331-01-540-4570 |
| Primary Part Number | 4-51-I-H-H-3-5-O-RING KIT 4"-51 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Core Industries Inc. Dba Mueller Steam Specialty |
| Status | ACTIVE |
| 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 |
|---|---|
| 4-51-I-H-H-3-5-O-RING KIT 4"-51 PRIMARY | Core Industries Inc. Dba Mueller Steam Specialty (USA) |
NSN 5331-01-540-4570 is a O-Ring, manufactured by Core Industries Inc. Dba Mueller Steam Specialty, classified under FSC 5331, O-ring. Status: active.
NSN 5331-01-540-4570 has 1 manufacturer part number on file: 4-51-I-H-H-3-5-O-RING KIT 4"-51 (Core Industries Inc. Dba Mueller Steam Specialty).
Key specifications for 4-51-I-H-H-3-5-O-RING KIT 4"-51: Special Features: THIS IS AN O-RING SET WHICH INCLUDES 2 STEM O-RINGS (REF NO'S 7&8 FROM THE BUTTERFLY VALVES PRICE LIST), SEAT O-RING (REF NO 10 FROM THE BUTTERFLY VALVES PRICE LIST), AND SET SCREW (REF NO 9 FROM THE BUTTERFLY VALVES PRICE LIST); Part Name Assigned by Controlling Agency: O-RING SET; End Item Identification: VALVE,BUTTERFLY,4.0 IN IN; Material: RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR. 1 specification is 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.