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NAS1191-04T4B
Machine Screw
Description
Fastener Length: 1/4", Thread: 4-40, Thread Length: 1/4", NAS1191 series screw
Specifications
| Fastener Length | 0.219 inches minimum and 0.250 inches maximum |
|---|---|
| Hardness Rating | 36.0 rockwell c minimum and 40.0 rockwell c maximum |
| Head Diameter | 0.178 inches minimum and 0.183 inches maximum |
| Head Height | 0.059 inches minimum and 0.069 inches maximum |
| Head Style | Flat chamfer |
| Internal Drive Style | Offset cruciform (torque set) |
| Length | 1/4 |
| Locking Feature | Patch threads |
| Material | Steel |
| Material Specification | Mil-s-5626 mil spec 1st material response or mil-s-5000 mil spec 2nd material response or mil-s-8503 mil spec 3rd material response or mil-s-6098 mil spec 4th material response or mil-s-6049 mil spec 5th material response |
| Min. Tensile Strength (psi) | 160000 pounds per square inch |
| Specification Data | 80205-nas1191 professional/industrial association standard |
| Surface Finish | 32.0 microinches bearing surface of head, 32.0 microinches threads |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Qq-p-416,ty 2,cl 2 fed spec single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.112 |
| Thread Direction | Right-hand |
| Thread Length | 0.169 inches minimum and 0.250 inches maximum |
| Thread Qty | 40 |
| Thread Qty Per Inch (tpi) | 40 |
| Thread Series Designator | UNJC |
| Thread Size | 4 |
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.
- NAS1101-04-4 NAS #4-40 · 1/4 in · Flat chamfer · Steel
- NAS1101E04-4 NAS #4-40 · 1/4 in · Flat chamfer
- NAS1101E04-4P NAS #4-40 · 1/4 in · Flat chamfer · Iron
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Catalog data updated 2026-07-05. Report a data error