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3M963-4L3
Screw
Description
Fastener Length: 21/32", Thread: 1/4-28, Thread Length: 29/64"
Specifications
| Countersink Angle | 99.0 degrees minimum and 101.0 degrees maximum |
|---|---|
| Fastener Length | 0.642 inches minimum and 0.672 inches maximum |
| Grip Diameter | 0.2485 inches minimum and 0.2495 inches maximum |
| Grip Length | 0.178 inches minimum and 0.198 inches maximum |
| Hardness Rating | 39.0 rockwell c minimum and 43.0 rockwell c maximum |
| Head Diameter | 0.3898 inches minimum and 0.3948 inches maximum |
| Head Style | Oval countersunk |
| Internal Drive Style | Offset cruciform (torque set) |
| Length | 43/64 |
| Material | Steel |
| Material Specification | Mil-s-6049 mil spec single material response |
| Min. Tensile Strength (psi) | 180000 pounds per square inch |
| Specification Data | 76301-3-963 manufacturers standard |
| Surface Finish | 32.0 microinches grip, 32.0 microinches threads |
| Surface Treatment | Aluminum |
| Surface Treatment Specification | Mil-c-83488,type 2 class 3 mil spec single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.444 inches minimum and 0.494 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.
- 3M963-4L3
- 3M963-4L4
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.
- 3M926-4L3 Commercial 1/4-28 · 0.672 in · Oval countersunk · Steel
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Catalog data updated 2026-07-05. Report a data error