The Screw,cap,socket Head, cataloged under National Stock Number 5305-00-005-0050, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Northrop Grumman Systems Corporation. Government technical data includes 20 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-005-0050 |
| Primary Part Number | A51K56639-11 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Northrop Grumman Systems Corporation |
| Status | ACTIVE |
| Width Across Flats | 0.140 INCHES MINIMUM AND 0.142 INCHES MAXIMUM IN |
| Head Height | 0.159 INCHES MINIMUM AND 0.164 INCHES MAXIMUM IN |
| Fastener Length | 0.984 INCHES MINIMUM AND 1.016 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 1.000 INCHES MAXIMUM IN |
| Hardness Rating | 80.0 ROCKWELL B MINIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.038 INCHES MINIMUM AND 0.043 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | 66 FED STD ALL MATERIAL RESPONSES OVERALL |
| Nominal Thread Diameter | 0.164 INCHES IN |
| Head Style | FLAT CHAMFER |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | PASSIVATE OVERALL |
| Minimum Yield Strength | 80000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL COMP 302 OR STEEL COMP 303 OR STEEL COMP 304 OR STEEL COMP 305 OR STEEL COMP 316 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 0.940 INCHES NOMINAL FIRST HOLE IN |
| Head Diameter | 0.262 INCHES MINIMUM AND 0.270 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 |
|---|---|
| A51K56639-11 PRIMARY | Northrop Grumman Systems Corporation (USA) |
| Reference | Meaning |
|---|---|
| A51K56639-11 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
| A51K56639-11 | 3/9 Design control — primary reference Northrop Grumman Systems Corporation Dba Northrop Grumman Systems Corp Div Northrop Grumman Aeronautics Systems |
| A51K56639-11 | 5/2 Secondary reference U.S. Government activity |
NSN 5305-00-005-0050 is a Screw,cap,socket Head, manufactured by Northrop Grumman Systems Corporation, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-005-0050 has 1 manufacturer part number on file: A51K56639-11 (Northrop Grumman Systems Corporation).
Key specifications for A51K56639-11: Width Across Flats: 0.140 INCHES MINIMUM AND 0.142 INCHES MAXIMUM IN; Head Height: 0.159 INCHES MINIMUM AND 0.164 INCHES MAXIMUM IN; Fastener Length: 0.984 INCHES MINIMUM AND 1.016 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL. 20 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.