The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-137-7293, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Div Tridair Products. 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-137-7293 |
| Primary Part Number | CA21155-4-6HS |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Howmet Global Fastening Systems Inc. Div Tridair Products |
| Status | ACTIVE |
| Width Across Flats | 0.156 INCHES MINIMUM AND 0.159 INCHES MAXIMUM IN |
| Fastener Length | 1.147 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-416 TYPE 2 CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.497 INCHES NOMINAL IN |
| Material Document and Classification | MIL-S-6049 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-5626 MIL SPEC 2ND MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP 8740 OR STEEL COMP 4140 OVERALL |
| Thread Series Designator | UNF |
| Head Diameter | 0.394 INCHES MINIMUM AND 0.404 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 |
|---|---|
| CA21155-4-6HS PRIMARY | Howmet Global Fastening Systems Inc. Div Tridair Products (USA) |
NSN 5305-01-137-7293 is a Screw,cap,socket Head, manufactured by Howmet Global Fastening Systems Inc. Div Tridair Products, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-137-7293 has 1 manufacturer part number on file: CA21155-4-6HS (Howmet Global Fastening Systems Inc. Div Tridair Products).
Key specifications for CA21155-4-6HS: Width Across Flats: 0.156 INCHES MINIMUM AND 0.159 INCHES MAXIMUM IN; Fastener Length: 1.147 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-416 TYPE 2 CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.497 INCHES NOMINAL IN. 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.