Spec hardware, served at warp speed.

bolts › machine bolts

MS9557-37

Military Standard Bolt

View quote list → Saved parts →

Description

Fastener Length: 3-1/8", Thread: 1/4-28, Thread Length: 51/64"

Specifications

Extended Washer Diameter 0.438
Extended Washer Thickness 0.060
Fastener Length 3.125
Features Provided Finished head
Grip Length 2.315 inches minimum and 2.375 inches maximum
Head Height 0.300
Head Style Double hexagon w/hole
Length 3 1/8
Material Iron
Material Specification Ams 5731 assn std single material response
Min. Tensile Strength (psi) 160000 pounds per square inch
Minimum Yield Strength 85000 pounds per square inch
Surface Finish 32.0 microinches bearing surface of head32.0 microinches grip32.0 microinches threads
Thread Class 3a
Thread Diameter 0.250
Thread Direction Right-hand
Thread Length 0.625 inches minimum and 0.810 inches maximum
Thread Qty 28
Thread Qty Per Inch (tpi) 28
Thread Series Designator UNJF
Thread Size 1/4
Width Between Flats 0.312

Cross-reference

No interchangeable or dimensionally similar parts are on record for MS9557-37. Try the cross-reference lookup to search by a different part number.

Catalog data updated 2026-07-05. Report a data error