The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-131-8167, 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-131-8167 |
| Primary Part Number | CA21128-4-1 |
| 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 | 0.141 INCHES NOMINAL IN |
| Head Height | 0.140 INCHES MINIMUM AND 0.172 INCHES MAXIMUM IN |
| Fastener Length | 1.230 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.510 INCHES NOMINAL IN |
| Material Document and Classification | AMS 5643 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Width Between Flats | 0.428 INCHES MINIMUM AND 0.440 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP 630 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| 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 |
|---|---|
| CA21128-4-1 PRIMARY | Howmet Global Fastening Systems Inc. Div Tridair Products (USA) |
| Reference | Meaning |
|---|---|
| PC91004-2 | 7/2 Vendor item drawing reference Rockwell Collins, Inc. Dba Rc Displays Systems |
NSN 5305-01-131-8167 is a Screw,cap,socket Head, manufactured by Howmet Global Fastening Systems Inc. Div Tridair Products, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-131-8167 has 1 manufacturer part number on file: CA21128-4-1 (Howmet Global Fastening Systems Inc. Div Tridair Products).
Key specifications for CA21128-4-1: Width Across Flats: 0.141 INCHES NOMINAL IN; Head Height: 0.140 INCHES MINIMUM AND 0.172 INCHES MAXIMUM IN; Fastener Length: 1.230 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL. 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.