The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-088-1968, 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 16 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 | 5305-01-088-1968 |
| Primary Part Number | CA21089-4-4HS |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Howmet Global Fastening Systems Inc. Div Tridair Products |
| Status | ACTIVE |
| Surface Finish | 32.0 MICROINCHES GRIP |
| Surface Finish | 32.0 MICROINCHES BEARING SURFACE OF HEAD |
| Width Across Flats | 0.156 INCHES MINIMUM AND 0.159 INCHES MAXIMUM IN |
| Fastener Length | 1.002 INCHES MINIMUM AND 1.012 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY2 CL2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.441 INCHES MINIMUM AND 0.661 INCHES MAXIMUM IN |
| Material Document and Classification | MIL-S-5626 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC 2ND MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP 4140 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNF |
| 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 |
|---|---|
| CA21089-4-4HS PRIMARY | Howmet Global Fastening Systems Inc. Div Tridair Products (USA) |
NSN 5305-01-088-1968 is a Screw,cap,socket Head, manufactured by Howmet Global Fastening Systems Inc. Div Tridair Products, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-088-1968 has 1 manufacturer part number on file: CA21089-4-4HS (Howmet Global Fastening Systems Inc. Div Tridair Products).
Key specifications for CA21089-4-4HS: Surface Finish: 32.0 MICROINCHES GRIP; Surface Finish: 32.0 MICROINCHES BEARING SURFACE OF HEAD; Width Across Flats: 0.156 INCHES MINIMUM AND 0.159 INCHES MAXIMUM IN; Fastener Length: 1.002 INCHES MINIMUM AND 1.012 INCHES MAXIMUM IN. 16 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.