The Washer,flat, cataloged under National Stock Number 5310-00-110-8978, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems. Government technical data includes 11 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-110-8978 |
| Primary Part Number | 133B6663-6 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems |
| Status | ACTIVE |
| Overall Diameter | 1.650 INCHES MINIMUM AND 1.700 INCHES MAXIMUM IN |
| Heat Treatment | ANNEALED |
| Hardness Rating | 30.0 ROCKWELL C MINIMUM AND 35.0 ROCKWELL C MAXIMUM |
| Material Document and Classification | MIL-S-18729 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | PHOSPHATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 4130 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.780 INCHES MINIMUM AND 0.800 INCHES MAXIMUM IN |
| Thickness | 0.250 INCHES NOMINAL 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 |
|---|---|
| 133B6663-6 PRIMARY | General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems (USA) |
NSN 5310-00-110-8978 is a Washer,flat, manufactured by General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-110-8978 has 1 manufacturer part number on file: 133B6663-6 (General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems).
Key specifications for 133B6663-6: Overall Diameter: 1.650 INCHES MINIMUM AND 1.700 INCHES MAXIMUM IN; Heat Treatment: ANNEALED; Hardness Rating: 30.0 ROCKWELL C MINIMUM AND 35.0 ROCKWELL C MAXIMUM; Material Document and Classification: MIL-S-18729 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL. 11 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.