The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-398-4948, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Hardware Specialty Co Inc. Government technical data includes 20 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-01-398-4948 |
| Primary Part Number | A3131794 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Hardware Specialty Co Inc |
| Status | ACTIVE |
| Width Across Flats | 0.156 INCHES NOMINAL IN |
| Fastener Length | 0.970 INCHES MINIMUM AND 1.000 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY 2 CL 3 FED SPEC SINGLE TREATMENT RESPONSE FASTENER |
| Thread Length | 0.709 INCHES MINIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM FASTENER |
| Material Document and Classification | FED-STD66 FED STD SINGLE MATERIAL RESPONSE FASTENER |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Locking Feature | PATCH THREADS |
| Surface Treatment | CADMIUM AND CHROMATE FASTENER |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Countersink Angle | 80.0 DEGREES MINIMUM AND 82.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | PLASTIC POLYAMIDE NYLON LOCKING FEATURE |
| Material | STEEL FASTENER |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.480 INCHES MINIMUM AND 0.531 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 |
|---|---|
| A3131794 | Hardware Specialty Co Inc (USA) |
| Reference | Meaning |
|---|---|
| A3131794 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-398-4948 is a Screw,cap,socket Head, manufactured by Hardware Specialty Co Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-398-4948 has 1 manufacturer part number on file: A3131794 (Hardware Specialty Co Inc).
Key specifications for A3131794: Width Across Flats: 0.156 INCHES NOMINAL IN; Fastener Length: 0.970 INCHES MINIMUM AND 1.000 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416 TY 2 CL 3 FED SPEC SINGLE TREATMENT RESPONSE FASTENER; Thread Length: 0.709 INCHES MINIMUM IN. 20 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.