The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-133-2181, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Oil States Industries, Inc. Div Special Products Div. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-133-2181 |
| Primary Part Number | 300103 ITEM 4 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Oil States Industries, Inc. Div Special Products Div |
| Status | ACTIVE |
| Width Across Flats | 0.250 INCHES NOMINAL IN |
| Head Height | 0.306 INCHES MINIMUM AND 0.312 INCHES MAXIMUM IN |
| Fastener Length | 1.210 INCHES MINIMUM AND 1.250 INCHES MAXIMUM IN |
| Thread Length | 1.120 INCHES MINIMUM IN |
| Material Document and Classification | QQ-N-286 CL A FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | FLAT CHAMFER |
| Thread Direction | RIGHT-HAND |
| Locking Feature | STRIP OR PELLET OR PATCH THREADS |
| Minimum Tensile Strength | 130000 POUNDS PER SQUARE INCH LBS |
| Minimum Yield Strength | 90000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 18 |
| Material | NICKEL ALLOY K-500 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.457 INCHES MINIMUM AND 0.469 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 |
|---|---|
| 300103 ITEM 4 PRIMARY | Oil States Industries, Inc. Div Special Products Div (USA) |
| 300074 ITEM 4 | Oil States Industries, Inc. Div Special Products Div (USA) |
| Reference | Meaning |
|---|---|
| 300103 ITEM 4 | 5/9 Secondary reference Edwards Aerospace Inc |
| 300074 ITEM 4 | 5/9 Secondary reference Edwards Aerospace Inc |
NSN 5305-01-133-2181 is a Screw,cap,socket Head, manufactured by Oil States Industries, Inc. Div Special Products Div, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-133-2181 has 2 manufacturer part numbers on file: 300103 ITEM 4 (Oil States Industries, Inc. Div Special Products Div), 300074 ITEM 4 (Oil States Industries, Inc. Div Special Products Div).
1 possible match (shared part number, not a government interchangeability claim): 5305-01-134-9764. Verify interchangeability with system specifications before substitution.
Key specifications for 300103 ITEM 4: Width Across Flats: 0.250 INCHES NOMINAL IN; Head Height: 0.306 INCHES MINIMUM AND 0.312 INCHES MAXIMUM IN; Fastener Length: 1.210 INCHES MINIMUM AND 1.250 INCHES MAXIMUM IN; Thread Length: 1.120 INCHES MINIMUM IN. 17 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.