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MS51959-98
5/16-18X1 MS51959 NASM51959 Phil Flat Machine Screw Full Thread 300 Series S/S DFAR
Description
Fastener Length: 63/64", Thread: 1/4-18, Thread Length: 3/4"
Specifications
| Countersink Angle | 80.0 degrees minimum and 82.0 degrees maximum |
|---|---|
| Diameter | 5/16 |
| Drive | Phillips |
| Drive Type | Phillips |
| Fastener Length | 0.969 inches minimum and 1.000 inches maximum |
| Finish | Passivate per QQ-P-35, Plain |
| Full Size | 5/16-18 x 1 |
| Head Diameter | 0.568 inches minimum and 0.635 inches maximum |
| Head Style | 82 Degree Flat Head, Flat countersunk, Phillips Flat Head |
| Head Type | Flat |
| Internal Drive Style | Cross recess type 1 |
| Length | 0 63/64, 1 |
| Material | CRES |
| Milspec Part | MS51959 |
| MilspecPart | MS51959 |
| Min. Tensile Strength (psi) | 80000 pounds per square inch |
| Screw Material | Steel corrosion resisting |
| Screw Material Specification | 66 fed std single material response |
| Screw Surface Treatment | Passivate |
| Screw Surface Treatment Specification | Qq-p-35 fed spec single treatment response |
| Size | 5/16-18 |
| Thread Class | 2a |
| Thread Diameter | 0.312 |
| Thread Direction | Right-hand |
| Thread Fraction | 5/16-18 |
| Thread Length | 0.809 inches minimum |
| Thread Qty | 18 |
| Thread Qty Per Inch (tpi) | 18 |
| Thread Series Designator | UNC |
| Thread Size | 1/4 |
| Thread Type | N.C. - Coarse, UNC-2A |
| Threads Per Inch | 18 |
| U.O.M. | Imperial |
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS51959-98. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error