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NAS6604-21

Close Tolerance Bolt

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Description

NAS6604 Shear Bolts Thread 1/4-28

Specifications

Alternate Part Number NAS1304-21
Country of Origin USA
Drilling Undrilled Head
Fastener Length 1.722 inches minimum and 1.752 inches maximum
Grip 1.312 in
Grip Diameter 0.2485 inches minimum and 0.2495 inches maximum
Grip Length 1.302 inches minimum and 1.322 inches maximum
Grip Tolerance ±0.010 in
Head Height 0.125 inches minimum and 0.140 inches maximum
Head Style Undercut hexagon
Head Type Hexagon
Industry Standards/Certification NAS6604
Length 1 3/4, 1.737 in
Material Steel
Material Specification Mil-s-5000 mil spec 1st material response or mil-s-6049 mil spec 2nd material response or ams6322 assn std 2nd material response
NIIN 01-160-7560
NSN 5306-01-160-7560
Surface Finish 32.0 microinches bearing surface of head, 32.0 microinches grip, 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 0.250
Thread Direction Right-hand
Thread Length 0.400 inches minimum and 0.450 inches maximum
Thread Qty 28
Thread Qty Per Inch (tpi) 28
Thread Series Designator UNJF
Thread Size 0.2500-28, 1/4
Weight 0.003 lb
Width Between Flats 0.430 inches minimum and 0.439 inches maximum

Cross-reference

Interchangeable

Parts that share a National Stock Number or are listed as an alternate for NAS6604-21 — functionally equivalent.

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