The Nut,plain,hexagon, cataloged under National Stock Number 5310-00-208-7787, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Ontic Engineering & Manufacturing, Inc Dba Ontic Us. Government technical data includes 17 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-208-7787 |
| Primary Part Number | R400-68A |
| Item Name | Nut,plain,hexagon |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Ontic Engineering & Manufacturing, Inc Dba Ontic Us |
| Status | ACTIVE |
| Width Across Flats | 0.678 INCHES MINIMUM AND 0.698 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNF |
| Hole Configuration Style | CONFIGURATION A |
| Material Document and Classification | QQ-B-611 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.500 INCHES IN |
| Nut Height | 0.177 INCHES MINIMUM AND 0.190 INCHES MAXIMUM IN |
| Drilled Hole Diameter | 0.0465 INCHES NOMINAL IN |
| Surface Treatment | CADMIUM OVERALL |
| Countersink Angle | 109.0 DEGREES MINIMUM AND 111.0 DEGREES MAXIMUM NUT |
| Nut Style | HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 20 |
| Material | COPPER ALLOY 360 OVERALL |
| Bearing Surface Type | CHAMFERED OR WASHER FACED |
| Hole Type and Quantity | 6 DRILLED |
| 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 |
|---|---|
| R400-68A PRIMARY | Ontic Engineering & Manufacturing, Inc Dba Ontic Us (USA) |
| Reference | Meaning |
|---|---|
| R400-68A | 5/9 Secondary reference Donallco Inc |
NSN 5310-00-208-7787 is a Nut,plain,hexagon, manufactured by Ontic Engineering & Manufacturing, Inc Dba Ontic Us, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-208-7787 has 1 manufacturer part number on file: R400-68A (Ontic Engineering & Manufacturing, Inc Dba Ontic Us).
Key specifications for R400-68A: Width Across Flats: 0.678 INCHES MINIMUM AND 0.698 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Series: UNF; Hole Configuration Style: CONFIGURATION A. 17 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.