bolts › close tolerance bolts
NAS1578C4R9
Bolt
Description
Fastener Length: 31/32", Thread: 1/4-28, Thread Length: 27/64"
Specifications
| Fastener Length | 0.950 inches minimum and 0.980 inches maximum |
|---|---|
| Grip Diameter | 0.2485 inches minimum and 0.2495 inches maximum |
| Grip Length | 0.552 inches minimum and 0.572 inches maximum |
| Head Diameter | 0.477 inches minimum and 0.492 inches maximum |
| Head Height | 0.140 inches minimum and 0.150 inches maximum |
| Head Style | Pan no. 2 |
| Internal Drive Style | Offset cruciform (torque set) |
| Length | 31/32 |
| Material | Iron |
| Material Specification | Ams5731 assn std single material response or ams5732 assn std single material response or ams5737 assn std single material response |
| Min. Tensile Strength (psi) | 160000 pounds per square inch |
| Special Features | Internal drive ribbed |
| Specification Data | 80205-nas1578 professional/industrial association standard |
| Surface Finish | 32.0 microinches bearing surface of head, 32.0 microinches grip, 32.0 microinches threads |
| Surface Treatment | Passivate |
| Surface Treatment Specification | Qq-p-35 fed spec single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.378 inches minimum and 0.428 inches maximum |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series Designator | UNJF |
| Thread Size | 1/4 |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
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.
- NAS1578A4R9 NAS 1/4-28 · 31/32 in · Pan no. 2 · Steel
- NAS1578V4R9 NAS 1/4-28 · 31/32 in · Pan no. 2 · Titanium
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Catalog data updated 2026-07-05. Report a data error