The Screw,cap,socket Head, cataloged under National Stock Number 5305-00-273-5301, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier. Government technical data includes 18 specifications, cited from the U.S. Government catalog. The record lists 7 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-00-273-5301 |
| Primary Part Number | 298233PC278 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier |
| Status | ACTIVE |
| Width Across Flats | 0.218 INCHES MINIMUM AND 0.220 INCHES MAXIMUM IN |
| Head Height | 0.306 INCHES MINIMUM AND 0.312 INCHES MAXIMUM IN |
| Fastener Length | 1.250 INCHES NOMINAL IN |
| Thread Length | 1.125 INCHES NOMINAL IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | QQ-S-624 FED SPEC ALL MATERIAL RESPONSES OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | FLAT CHAMFER |
| Thread Direction | RIGHT-HAND |
| Nondefinitive Spec/std Data | 1 TYPE AND 11 STYLE |
| Surface Treatment | ZINC OVERALL |
| Minimum Yield Strength | 140000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 18 |
| Material | STEEL COMP 4135 OR STEEL COMP 4137 OR STEEL COMP 8635 OR STEEL COMP 8640 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.429 INCHES MINIMUM AND 0.437 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 |
|---|---|
| 298233PC278 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 166254PC12 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 43-S-4367-70 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 709174PC108 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 200074PC16 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 279225PC39 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| 12Z51PC347 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| Reference | Meaning |
|---|---|
| FFS86TYPE1STYLE11 | 4/1 Identification reference U.S. Government activity |
NSN 5305-00-273-5301 is a Screw,cap,socket Head, manufactured by Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-273-5301 has 7 manufacturer part numbers on file: 298233PC278 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier), 166254PC12 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier), 43-S-4367-70 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier), 709174PC108 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier), 200074PC16 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier) and 2 more.
Key specifications for 298233PC278: Width Across Flats: 0.218 INCHES MINIMUM AND 0.220 INCHES MAXIMUM IN; Head Height: 0.306 INCHES MINIMUM AND 0.312 INCHES MAXIMUM IN; Fastener Length: 1.250 INCHES NOMINAL IN; Thread Length: 1.125 INCHES NOMINAL IN. 18 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.