The Screw,externally Relieved Body, cataloged under National Stock Number 5305-00-142-4186, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Bisco Industries Inc Dba National Precision Products Company Div National Precision Products. Government technical data includes 21 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-00-142-4186 |
| Primary Part Number | 606343-1 |
| Item Name | Screw,externally Relieved Body |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Bisco Industries Inc Dba National Precision Products Company Div National Precision Products |
| Status | ACTIVE |
| Head Height | 0.150 INCHES MINIMUM AND 0.163 INCHES MAXIMUM IN |
| Fastener Length | 1.730 INCHES MINIMUM AND 1.770 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.530 INCHES MINIMUM AND 0.570 INCHES MAXIMUM IN |
| Hardness Rating | 32.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | SAE GR 8 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| First Diameter From Head | 0.245 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN |
| Distance From Largest Bearing Surface of Head to End of Second Diameter | 1.160 INCHES MINIMUM AND 1.240 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Second Diameter From Head | 0.177 INCHES MINIMUM AND 0.187 INCHES MAXIMUM IN |
| Width Between Flats | 0.428 INCHES MINIMUM AND 0.438 INCHES MAXIMUM IN |
| Distance From Largest Bearing Surface of Head to End of First Diameter | 0.160 INCHES MINIMUM AND 0.200 INCHES MAXIMUM IN |
| Externally Relieved Body Diameter Quantity | 1 |
| Surface Treatment | CADMIUM OVERALL |
| Internal Drive Style | W/O INTERNAL DRIVE |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 20 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| 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 |
|---|---|
| 606343-1 | Bisco Industries Inc Dba National Precision Products Company Div National Precision Products (USA) |
| Reference | Meaning |
|---|---|
| 606343-1 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-00-142-4186 is a Screw,externally Relieved Body, manufactured by Bisco Industries Inc Dba National Precision Products Company Div National Precision Products, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-142-4186 has 1 manufacturer part number on file: 606343-1 (Bisco Industries Inc Dba National Precision Products Company Div National Precision Products).
Key specifications for 606343-1: Head Height: 0.150 INCHES MINIMUM AND 0.163 INCHES MAXIMUM IN; Fastener Length: 1.730 INCHES MINIMUM AND 1.770 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.530 INCHES MINIMUM AND 0.570 INCHES MAXIMUM IN. 21 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.