The Washer,recessed, cataloged under National Stock Number 5310-01-042-8874, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Leonardo Spa Aeronautics Division - Pomigliano D'arco Site. Government technical data includes 12 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5310-01-042-8874 |
| Primary Part Number | NTA11551-4C |
| Item Name | Washer,recessed |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Leonardo Spa Aeronautics Division - Pomigliano D'arco Site |
| Status | ACTIVE |
| Surface Treatment Document and Classification | AMS 2416 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM |
| Style Designator | RECESSED |
| Material Document and Classification | MIL-S-18729 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-18728 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-18733 MIL SPEC 3RD MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.475 INCHES MINIMUM AND 0.495 INCHES MAXIMUM IN |
| Material Thickness | 0.057 INCHES MINIMUM AND 0.069 INCHES MAXIMUM IN |
| Specification/standard Data | 81205-BACW10BP MANUFACTURERS STANDARD |
| Recess Diameter | 0.332 INCHES MINIMUM AND 0.352 INCHES MAXIMUM IN |
| Surface Treatment | NICKEL AND CADMIUM OVERALL |
| Material | STEEL COMP 4130 OR STEEL COMP 8630 OR STEEL COMP 4135 OVERALL |
| Hole Diameter | 0.250 INCHES MINIMUM AND 0.261 INCHES MAXIMUM IN |
| Recess Angle | 90.0 DEGREES MINIMUM AND 100.0 DEGREES MAXIMUM |
| 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 |
|---|---|
| NTA11551-4C | Leonardo Spa Aeronautics Division - Pomigliano D'arco Site (ITA) |
| BACW10BP4C | Boeing Defence Australia Ltd (AUS) |
| BACW10BP4C | Boeing Defence Australia Ltd Div Defense, Space & Security (AUS) |
| Reference | Meaning |
|---|---|
| BACW10BP4C | 3/2 Design control — primary reference U.S. Government activity |
NSN 5310-01-042-8874 is a Washer,recessed, manufactured by Leonardo Spa Aeronautics Division - Pomigliano D'arco Site, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-042-8874 has 3 manufacturer part numbers on file: NTA11551-4C (Leonardo Spa Aeronautics Division - Pomigliano D'arco Site), BACW10BP4C (Boeing Defence Australia Ltd), BACW10BP4C (Boeing Defence Australia Ltd Div Defense, Space & Security).
1 possible match (shared part number, not a government interchangeability claim): 5310-01-669-7035. Verify interchangeability with system specifications before substitution.
Key specifications for NTA11551-4C: Surface Treatment Document and Classification: AMS 2416 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Hardness Rating: 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM; Style Designator: RECESSED; Material Document and Classification: MIL-S-18729 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-18728 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-18733 MIL SPEC 3RD MATERIAL RESPONSE OVERALL. 12 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.