The Washer,flat, cataloged under National Stock Number 5310-01-186-7783, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. Government technical data includes 11 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 5310-01-186-7783 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Status | ACTIVE |
| Width Across Flats | 1.500 INCHES NOMINAL IN |
| Overall Diameter | 3.000 INCHES NOMINAL IN |
| Criticality Code Justification | ZZZY |
| Material Document and Classification | QQ-S-766 CL 430,COND A FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND W/FLATS |
| Material | STEEL COMP 430 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 1.062 INCHES NOMINAL IN |
| Reference Number Differentiating Characteristics | MATERIAL WILL BE IN ACCORDANCE WITH SHIPS PARTS CONTROL CENTER ACTIVITY HX QUALITY CONTROL,MANUFACTURING AND TESTING SPECIFICATIONS |
| Thickness | 0.062 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 | C |
| Reference | Meaning |
|---|---|
| 4874-F-31 | 3/1 Design control — primary reference Atwood & Morrill Co., Inc. Dba Weir Valves and Controls Usa |
| 4874-F | 5/1 Secondary reference Atwood & Morrill Co., Inc. Dba Weir Valves and Controls Usa |
NSN 5310-01-186-7783 is a Washer,flat, classified under FSC 5310, Nuts and Washers. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 5310-01-186-7784, 5310-01-186-7785. Verify interchangeability with system specifications before substitution.
Key specifications for 5310-01-186-7783: Width Across Flats: 1.500 INCHES NOMINAL IN; Overall Diameter: 3.000 INCHES NOMINAL IN; Criticality Code Justification: ZZZY; Material Document and Classification: QQ-S-766 CL 430,COND A FED 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.