The Thumbscrew, cataloged under National Stock Number 5305-01-671-4121, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Unac. Government technical data includes 6 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-671-4121 |
| Primary Part Number | A20504 |
| Item Name | Thumbscrew |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Unac |
| Status | ACTIVE |
| Fastener Length | 42.0 MILLIMETERS NOMINAL MM |
| Bottom Countersink Diameter | 6.0 MILLIMETERS NOMINAL MM |
| Tee Head Flange Thickness | 2.0 MILLIMETERS NOMINAL MM |
| Color | BLACK OVERALL |
| Surface Treatment | BLACK CHEMICAL FINISH OVERALL |
| Head Diameter | 12.0 MILLIMETERS NOMINAL MM |
| 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 |
|---|---|
| A20504 | Unac (FRA) |
| Reference | Meaning |
|---|---|
| 12602792 | 5/9 Secondary reference Oshkosh Defense Llc |
| 12602792 | 7/2 Vendor item drawing reference U S Army Tank Automotive Command Amsta-Im-Mm |
| D8-316-418-191 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-671-4121 is a Thumbscrew, manufactured by Unac, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-671-4121 has 1 manufacturer part number on file: A20504 (Unac).
Key specifications for A20504: Fastener Length: 42.0 MILLIMETERS NOMINAL MM; Bottom Countersink Diameter: 6.0 MILLIMETERS NOMINAL MM; Tee Head Flange Thickness: 2.0 MILLIMETERS NOMINAL MM; Color: BLACK OVERALL. 6 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.