The Screw,shoulder, cataloged under National Stock Number 5305-01-536-4447, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace. Government technical data includes 25 specifications, cited from the U.S. Government catalog. The record lists 17 manufacturer part numbers 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-536-4447 |
| Primary Part Number | 3M1278E4D7A |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace |
| Status | ACTIVE |
| Spline Minor Diameter | 0.1105 INCHES MINIMUM AND 0.1125 INCHES MAXIMUM IN |
| Fastener Length | 0.8475 INCHES MINIMUM AND 0.8775 INCHES MAXIMUM IN |
| Shoulder Length | 0.3775 INCHES NOMINAL GRIP IN |
| Surface Treatment Document and Classification | MIL-L-87132 TYPE 1 GRADE B MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Shoulder Diameter | 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM GRIP IN |
| Thread Length | 0.425 INCHES NOMINAL IN |
| Shoulder Shape | ROUND GRIP |
| Criticality Code Justification | AGAV |
| Material Document and Classification | AMS5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Spline Major Diameter | 0.1540 INCHES MINIMUM AND 0.1560 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.2500 INCHES IN |
| Features Provided | CETYL ALCOHOL LUBRICANT |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | TORX |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | NICKEL ALLOY 718 OVERALL |
| Hole Quantity | 1 |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Type | DRILLED |
| Hole Diameter | 0.076 INCHES MINIMUM AND 0.086 INCHES MAXIMUM IN |
| Head Diameter | 0.388 INCHES MINIMUM AND 0.395 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 | Y |
| Part Number | Manufacturer |
|---|---|
| TX1027E4D7YA | Howmet Global Fastening Systems Inc (USA) |
| 3M1278E4D7A PRIMARY | B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace (USA) |
| 3M1278E4D7A | Houston Precision Fasteners I Lp (USA) |
| TX1027E4D7YA | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| 3M1278E4D7A PRIMARY | The Boeing Company Div Defense (USA) |
| TX1027E4D7YA PRIMARY | Huck International, Inc (USA) |
| TX1027E4D7YA | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| 3M1278E4D7A PRIMARY | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| TX1027E4D7YA | Sps Technologies, Llc Dba PB Fasteners (USA) |
| TX1027E4D7YA | Hi-Shear Corporation (USA) |
| 3M1278E4D7A PRIMARY | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| 3M1278E4D7A PRIMARY | Saturn Fasteners Inc (USA) |
| TX1027E4D7YA | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| 3M1278E4D7A PRIMARY | Heartland Precision Fasteners Inc (USA) |
| 3M1278E4D7A | Camcar Llc Div Camcar Llc (USA) |
| WC1278E4D7A | West Coast Aerospace, Inc. (USA) |
| 11863E4D7A | Reid Products Inc. Dba Reid Products Inc (USA) |
| Reference | Meaning |
|---|---|
| TX1027E4D7YA | 5/2 Secondary reference U.S. Government activity |
| TX1027E4D7YA | 3/2 Design control — primary reference U.S. Government activity |
| TX1027E4D7YA | 5/9 Secondary reference Sps Technologies Inc |
NSN 5305-01-536-4447 is a Screw,shoulder, manufactured by B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-536-4447 has 17 manufacturer part numbers on file: TX1027E4D7YA (Howmet Global Fastening Systems Inc), 3M1278E4D7A (B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace), 3M1278E4D7A (Houston Precision Fasteners I Lp), TX1027E4D7YA (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), 3M1278E4D7A (The Boeing Company Div Defense) and 12 more.
Key specifications for 3M1278E4D7A: Spline Minor Diameter: 0.1105 INCHES MINIMUM AND 0.1125 INCHES MAXIMUM IN; Fastener Length: 0.8475 INCHES MINIMUM AND 0.8775 INCHES MAXIMUM IN; Shoulder Length: 0.3775 INCHES NOMINAL GRIP IN; Surface Treatment Document and Classification: MIL-L-87132 TYPE 1 GRADE B MIL SPEC SINGLE TREATMENT RESPONSE OVERALL. 25 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.