The Washer,flat, cataloged under National Stock Number 5310-01-155-9823, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Leonardo Spa Helicopters Division - Production Site. Government technical data includes 12 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-155-9823 |
| Primary Part Number | BACW10DH4 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Leonardo Spa Helicopters Division - Production Site |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TY 2,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Overall Diameter | 0.521 INCHES MINIMUM AND 0.541 INCHES MAXIMUM IN |
| Hardness Rating | 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM |
| Material Document and Classification | MIL-S-6758 MIL SPEC SINGLE MATERIAL RESPONSE OR MIL-S-18729 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Specification/standard Data | 81205-BACW10DH MANUFACTURERS STANDARD |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 4130 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.252 INCHES MINIMUM AND 0.260 INCHES MAXIMUM IN |
| Thickness | 0.052 INCHES MINIMUM AND 0.072 INCHES MAXIMUM IN |
| 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 |
|---|---|
| BACW10DH4 | Leonardo Spa Helicopters Division - Production Site (ITA) |
| Reference | Meaning |
|---|---|
| BACW10DH-4 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5310-01-155-9823 is a Washer,flat, manufactured by Leonardo Spa Helicopters Division - Production Site, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-155-9823 has 1 manufacturer part number on file: BACW10DH4 (Leonardo Spa Helicopters Division - Production Site).
Key specifications for BACW10DH4: Surface Treatment Document and Classification: QQ-P-416,TY 2,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Overall Diameter: 0.521 INCHES MINIMUM AND 0.541 INCHES MAXIMUM IN; Hardness Rating: 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM; Material Document and Classification: MIL-S-6758 MIL SPEC SINGLE MATERIAL RESPONSE OR MIL-S-18729 MIL SPEC SINGLE 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.