The Washer,shouldered and Recessed, cataloged under National Stock Number 5310-00-778-0590, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Ward Leonard Ct Llc. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-778-0590 |
| Primary Part Number | 916A |
| Item Name | Washer,shouldered and Recessed |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Ward Leonard Ct Llc |
| Status | ACTIVE |
| Style Designator | SHOULDERED AND RECESSED |
| Outside Diameter | 0.635 INCHES NOMINAL IN |
| Material Thickness | 0.022 INCHES NOMINAL IN |
| Shoulder Diameter | 0.395 INCHES NOMINAL IN |
| Material | COPPER ALLOY OVERALL |
| Hole Diameter | 0.170 INCHES NOMINAL IN |
| Recess Angle | 30.0 DEGREES NOMINAL |
| 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 |
|---|---|
| 916A PRIMARY | Ward Leonard Ct Llc (USA) |
| Reference | Meaning |
|---|---|
| 23480-36 | 5/9 Secondary reference Hickok Waekon Llc |
NSN 5310-00-778-0590 is a Washer,shouldered and Recessed, manufactured by Ward Leonard Ct Llc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-778-0590 has 1 manufacturer part number on file: 916A (Ward Leonard Ct Llc).
2 possible matches (shared part number, not a government interchangeability claim): 6625-01-343-3441, 4920-01-432-2112. Verify interchangeability with system specifications before substitution.
Key specifications for 916A: Style Designator: SHOULDERED AND RECESSED; Outside Diameter: 0.635 INCHES NOMINAL IN; Material Thickness: 0.022 INCHES NOMINAL IN; Shoulder Diameter: 0.395 INCHES NOMINAL IN. 7 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.