The Screw,close Tolerance, cataloged under National Stock Number 5305-01-537-3783, 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 24 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 | 5305-01-537-3783 |
| Primary Part Number | CA21351-5-6RS |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Howmet Global Fastening Systems Inc. Div Tridair Products |
| Status | ACTIVE |
| Point Diameter | 0.267 INCHES MINIMUM AND 0.272 INCHES MAXIMUM IN |
| Point Length | 0.100 INCHES NOMINAL IN |
| Fastener Length | 1.302 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | AMS QQ-P-35 NATIONAL STD/SPEC ALL TREATMENT RESPONSES OVERALL |
| Thread Length | 0.722 INCHES MINIMUM AND 0.771 INCHES MAXIMUM IN |
| Supplementary Features | STUD BOLTS SHALL HAVE POLYPROPLENE HEAD PROTECTIVE RING INSTALLED FOR SHIPPING, CUSTOMER TO REMOVE RING BEFORE INSTALLING |
| Material Document and Classification | MS 5731 NATIONAL STD/SPEC SINGLE MATERIAL RESPONSE OR AMS 5737 NATIONAL STD/SPEC 2ND MATERIAL RESPONSE OVERALL |
| Point Chamfer Angle | 45.0 DEGREES NOMINAL |
| Single Shear Strength | ERR-060 |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Point Style | CHAMFER DOG |
| Grip Length | 0.291 INCHES MINIMUM AND 0.430 INCHES MAXIMUM IN |
| Grip Diameter | 0.311 INCHES MINIMUM AND 0.312 INCHES MAXIMUM IN |
| Locking Feature | DETENT RING LOCKING FEATURE |
| Surface Treatment | PASSIVATE OVERALL |
| Minimum Tensile Strength | 4600 POUNDS PER SQUARE INCH LBS |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 100.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | IRON ALLOY 660 OVERALL |
| Thread Series Designator | UNF |
| Head Diameter | 0.542 INCHES NOMINAL 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 |
|---|---|
| CA21351-5-6RS PRIMARY | Howmet Global Fastening Systems Inc. Div Tridair Products (USA) |
NSN 5305-01-537-3783 is a Screw,close Tolerance, manufactured by Howmet Global Fastening Systems Inc. Div Tridair Products, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-537-3783 has 1 manufacturer part number on file: CA21351-5-6RS (Howmet Global Fastening Systems Inc. Div Tridair Products).
Key specifications for CA21351-5-6RS: Point Diameter: 0.267 INCHES MINIMUM AND 0.272 INCHES MAXIMUM IN; Point Length: 0.100 INCHES NOMINAL IN; Fastener Length: 1.302 INCHES NOMINAL IN; Surface Treatment Document and Classification: AMS QQ-P-35 NATIONAL STD/SPEC ALL TREATMENT RESPONSES OVERALL. 24 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.