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NAS1801-4-20
Hex Head Screw
Description
Hex Head Screw
Specifications
| Country of Origin | USA |
|---|---|
| Fastener Length | Between 1.234 inches and 1.281 inches |
| Head Height | Between 0.125 inches and 0.140 inches |
| Head Style | Hexagon Head |
| Internal Drive Style | Cross recess type 1 |
| Material | Steel |
| Material Specification | Mil-s-5000 military specification 1st material response or mil-s-6049 military specification 2nd material response or ams 6322 assn standard 2nd material response |
| Min. Tensile Strength (psi) | 160000 pounds per square inch |
| NIIN | 01-212-4522 |
| NSN | 5305-01-212-4522 |
| Sold In | Per Package |
| Specification Data | 80205-nas1801 professional/industrial association standard |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Cl 2 federal specification single treatment response type 2 qq-p-416 |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | Between 1.170 inches and 1.249 inches |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNJF |
| Thread Series Designator | Unjf (fine thread with external controlled root radius) |
| Thread Size | 1/4 |
| Weight | .005 lb |
| Width Between Flats | Between 0.367 inches and 0.376 inches |
Cross-reference
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- NAS1802-4-20 NAS 1/4-28 · 1.28 in · Hexagon Head · Iron
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Catalog data updated 2026-07-05. Report a data error