Thread & Dimensions
A internal thread (Class 3B)
1/4-20 UNC
B external thread (Class 3A)
5/16-24 UNF
Ø max minor special
.2785
Ø C (+.008/-.002)
.252
D (+.015/-.000)
.095
F
.240
G (±.010)
.380
J (±1)
24
Through-hole preparation
Min. full THD depth .519; Min. full depth .415
Blind-hole preparation
Min. full THD depth .519; Min. full depth .415
Material & Finish
Material
Alloy Steel 4130 per AMS 6370
Finish
Cadmium Plated per AMS-QQ-P-416 Type 2, Class 3 & SFL per SAE AS5272
Temperature range
Up to 450+°F
Heat treat
RC 25-34
Magnetic
YES
Crownserts is offering part CS420AD as factory new.