The Washer,flat, cataloged under National Stock Number 5310-01-138-4655, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Twin Disc, Incorporated Dba Twin Disc Mid-Atlantic. Government technical data includes 10 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 | 5310-01-138-4655 |
| Primary Part Number | A2888CH |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Twin Disc, Incorporated Dba Twin Disc Mid-Atlantic |
| Status | ACTIVE |
| Overall Diameter | 0.911 INCHES MINIMUM AND 0.932 INCHES MAXIMUM IN |
| Hardness Rating | 88.08 ROCKWELL SUPERFICIAL 15-N MINIMUM AND 92.0 ROCKWELL SUPERFICIAL 15-N MAXIMUM |
| Material Document and Classification | SAE ASSN STD ALL MATERIAL RESPONSES OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Features Provided | CASEHARDENED |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 1010 OR STEEL COMP 1012 OR STEEL COMP 1015 OR STEEL COMP 1016 OR STEEL COMP 1017 OR STEEL COMP 1018 OR STEEL COMP 1019 OR STEEL COMP 1020 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.458 INCHES MINIMUM AND 0.479 INCHES MAXIMUM IN |
| Thickness | 0.051 INCHES MINIMUM AND 0.081 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 |
|---|---|
| A2888CH PRIMARY | Twin Disc, Incorporated Dba Twin Disc Mid-Atlantic (USA) |
NSN 5310-01-138-4655 is a Washer,flat, manufactured by Twin Disc, Incorporated Dba Twin Disc Mid-Atlantic, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-138-4655 has 1 manufacturer part number on file: A2888CH (Twin Disc, Incorporated Dba Twin Disc Mid-Atlantic).
Key specifications for A2888CH: Overall Diameter: 0.911 INCHES MINIMUM AND 0.932 INCHES MAXIMUM IN; Hardness Rating: 88.08 ROCKWELL SUPERFICIAL 15-N MINIMUM AND 92.0 ROCKWELL SUPERFICIAL 15-N MAXIMUM; Material Document and Classification: SAE ASSN STD ALL MATERIAL RESPONSES OVERALL; Cross-Sectional Shape Style: RECTANGULAR. 10 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.