The Screw,assembled Washer, cataloged under National Stock Number 5305-00-018-7993, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Asap Semiconductor, Llc Dba Asap Semiconductor. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 6 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-018-7993 |
| Primary Part Number | 187993 |
| Item Name | Screw,assembled Washer |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Asap Semiconductor, Llc Dba Asap Semiconductor |
| Status | ACTIVE |
| Head Height | 0.208 INCHES MINIMUM AND 0.230 INCHES MAXIMUM IN |
| Fastener Length | 0.719 INCHES MINIMUM AND 0.750 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| Primary Washer Outside Diameter | 0.567 INCHES MINIMUM AND 0.590 INCHES MAXIMUM IN |
| Thread Length | 0.608 INCHES MINIMUM AND 0.719 INCHES MAXIMUM IN |
| Material Document and Classification | SAE ASSN STD ALL MATERIAL RESPONSES OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | HEXAGON |
| Primary Washer Style | FLAT EXTERNAL TEETH |
| Thread Direction | RIGHT-HAND |
| Primary Washer Material Thickness | 0.028 INCHES MINIMUM AND 0.034 INCHES MAXIMUM IN |
| Width Between Flats | 0.491 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OR ZINC OVERALL |
| Internal Drive Style | SLOT |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 18 |
| Material | STEEL COMP 1010 OR STEEL COMP 1020 OR STEEL COMP 1050 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Washer Quantity | 1 |
| 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 |
|---|---|
| 187993 | Asap Semiconductor, Llc Dba Asap Semiconductor (USA) |
| 187993 | Astral Air Parts Inc (USA) |
| 187993 | General Motors Llc Dba General Motors Llc (USA) |
| 187993 | Parttarget Inc. (USA) |
| 187993 | Aerobase Group Inc (USA) |
| 187993 | Army Weapons Command Attn Amswe-Ree-S (USA) |
| Reference | Meaning |
|---|---|
| 187993 | 5/9 Secondary reference Diamond Reo Truck Co |
| 5305000187993 | 6/9 Informative reference only E.c.a Etablissement Central Des Approvisionnements Des Forces Armees Royales |
| 187993 | 5/9 Secondary reference General Motors Corp |
| 187993 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-00-018-7993 is a Screw,assembled Washer, manufactured by Asap Semiconductor, Llc Dba Asap Semiconductor, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-018-7993 has 6 manufacturer part numbers on file: 187993 (Asap Semiconductor, Llc Dba Asap Semiconductor), 187993 (Astral Air Parts Inc), 187993 (General Motors Llc Dba General Motors Llc), 187993 (Parttarget Inc.), 187993 (Aerobase Group Inc) and 1 more.
Key specifications for 187993: Head Height: 0.208 INCHES MINIMUM AND 0.230 INCHES MAXIMUM IN; Fastener Length: 0.719 INCHES MINIMUM AND 0.750 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL; Primary Washer Outside Diameter: 0.567 INCHES MINIMUM AND 0.590 INCHES MAXIMUM IN. 19 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.