The Screw,shoulder, cataloged under National Stock Number 5305-01-180-3971, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Lockheed Martin Corporation Div Rms - Manassas. Government technical data includes 21 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 | 5305-01-180-3971 |
| Primary Part Number | 2868263-1 |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Lockheed Martin Corporation Div Rms - Manassas |
| Status | ACTIVE |
| Width Across Flats | 0.156 INCHES NOMINAL IN |
| Head Height | 0.209 INCHES MINIMUM AND 0.219 INCHES MAXIMUM IN |
| Fastener Length | 0.923 INCHES MINIMUM AND 0.933 INCHES MAXIMUM IN |
| Shoulder Length | 0.445 INCHES MINIMUM AND 0.455 INCHES MAXIMUM ALL SHOULDERS IN |
| Surface Treatment Document and Classification | QQ-P-416,TY2,CL3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Shoulder Diameter | 0.308 INCHES MINIMUM AND 0.310 INCHES MAXIMUM ALL SHOULDERS IN |
| Thread Length | 0.418 INCHES MINIMUM AND 0.438 INCHES MAXIMUM IN |
| Shoulder Shape | ROUND FIRST SHOULDER |
| Hardness Rating | 32.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | 66 FED STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLUSH |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | STEEL COMP 4037 OR STEEL COMP 8630 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.419 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 |
|---|---|
| 2868263-1 PRIMARY | Lockheed Martin Corporation Div Rms - Manassas (USA) |
NSN 5305-01-180-3971 is a Screw,shoulder, manufactured by Lockheed Martin Corporation Div Rms - Manassas, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-180-3971 has 1 manufacturer part number on file: 2868263-1 (Lockheed Martin Corporation Div Rms - Manassas).
Key specifications for 2868263-1: Width Across Flats: 0.156 INCHES NOMINAL IN; Head Height: 0.209 INCHES MINIMUM AND 0.219 INCHES MAXIMUM IN; Fastener Length: 0.923 INCHES MINIMUM AND 0.933 INCHES MAXIMUM IN; Shoulder Length: 0.445 INCHES MINIMUM AND 0.455 INCHES MAXIMUM ALL SHOULDERS IN. 21 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.