The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-266-9201, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Timken Gears & Services Inc. Div Philadelphia Gear. Government technical data includes 16 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-266-9201 |
| Primary Part Number | 170A779-034 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Timken Gears & Services Inc. Div Philadelphia Gear |
| Status | ACTIVE |
| Width Across Flats | 0.188 INCHES NOMINAL IN |
| Fastener Length | 0.750 INCHES NOMINAL IN |
| Thread Length | 0.441 INCHES MINIMUM IN |
| Hardness Rating | 32.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM FASTENER |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Locking Feature | PELLET THREADS |
| Internal Drive Style | HEXAGON |
| Countersink Angle | 80.0 DEGREES MINIMUM AND 82.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 18 |
| Material | PLASTIC LOCKING FEATURE |
| Material | STEEL FASTENER |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.356 INCHES MINIMUM AND 0.600 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 |
|---|---|
| 170A779-034 PRIMARY | Timken Gears & Services Inc. Div Philadelphia Gear (USA) |
| Reference | Meaning |
|---|---|
| 170A779-034 | 5/9 Secondary reference General Electric Company |
NSN 5305-01-266-9201 is a Screw,cap,socket Head, manufactured by Timken Gears & Services Inc. Div Philadelphia Gear, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-266-9201 has 1 manufacturer part number on file: 170A779-034 (Timken Gears & Services Inc. Div Philadelphia Gear).
Key specifications for 170A779-034: Width Across Flats: 0.188 INCHES NOMINAL IN; Fastener Length: 0.750 INCHES NOMINAL IN; Thread Length: 0.441 INCHES MINIMUM IN; Hardness Rating: 32.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM FASTENER. 16 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.