The Washer,key, cataloged under National Stock Number 5310-00-271-3178, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Caterpillar Inc Div Caterpillar Defense. Government technical data includes 8 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 | 5310-00-271-3178 |
| Primary Part Number | 5F4338 |
| Item Name | Washer,key |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Caterpillar Inc Div Caterpillar Defense |
| Status | ACTIVE |
| Overall Distance Including Keys | 1.625 INCHES NOMINAL1.625 INCHES NOMINAL IN |
| Style Designator | KEYKEY |
| Outside Diameter | 1.188 INCHES NOMINAL1.188 INCHES NOMINAL IN |
| Material Thickness | 0.188 INCHES NOMINAL0.188 INCHES NOMINAL IN |
| External Straight Key Width | 0.495 INCHES MAXIMUM0.495 INCHES MAXIMUM IN |
| External Key Quantity | 44 |
| Material | STEEL OVERALL |
| Hole Diameter | 0.688 INCHES NOMINAL0.688 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 |
|---|---|
| 5F4338 PRIMARY | Caterpillar Inc Div Caterpillar Defense (USA) |
NSN 5310-00-271-3178 is a Washer,key, manufactured by Caterpillar Inc Div Caterpillar Defense, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-271-3178 has 1 manufacturer part number on file: 5F4338 (Caterpillar Inc Div Caterpillar Defense).
Key specifications for 5F4338: Overall Distance Including Keys: 1.625 INCHES NOMINAL1.625 INCHES NOMINAL IN; Style Designator: KEYKEY; Outside Diameter: 1.188 INCHES NOMINAL1.188 INCHES NOMINAL IN; Material Thickness: 0.188 INCHES NOMINAL0.188 INCHES NOMINAL IN. 8 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.