The Washer,lock, cataloged under National Stock Number 5310-01-178-1951, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Fairbanks Morse, Llc. Government technical data includes 6 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-178-1951 |
| Primary Part Number | 91100303N |
| Item Name | Washer,lock |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Fairbanks Morse, Llc |
| Status | ACTIVE |
| Hardness Rating | 40.0 ROCKWELL C MINIMUM AND 50.0 ROCKWELL C MAXIMUM |
| Style Designator | FLAT EXTERNAL TEETH |
| Outside Diameter | 1.220 INCHES MINIMUM AND 1.260 INCHES MAXIMUM IN |
| Material Thickness | 0.047 INCHES MINIMUM AND 0.055 INCHES MAXIMUM IN |
| Material | STEEL OVERALL |
| Hole Diameter | 0.768 INCHES MINIMUM AND 0.795 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 |
|---|---|
| 91100303N PRIMARY | Fairbanks Morse, Llc (USA) |
| Reference | Meaning |
|---|---|
| 91100303 | 5/9 Secondary reference U.S. Government activity |
| 91100303N | 3/9 Design control — primary reference U.S. Government activity |
NSN 5310-01-178-1951 is a Washer,lock, manufactured by Fairbanks Morse, Llc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-178-1951 has 1 manufacturer part number on file: 91100303N (Fairbanks Morse, Llc).
Key specifications for 91100303N: Hardness Rating: 40.0 ROCKWELL C MINIMUM AND 50.0 ROCKWELL C MAXIMUM; Style Designator: FLAT EXTERNAL TEETH; Outside Diameter: 1.220 INCHES MINIMUM AND 1.260 INCHES MAXIMUM IN; Material Thickness: 0.047 INCHES MINIMUM AND 0.055 INCHES MAXIMUM IN. 6 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.