These custom captive shoulder screws were manufactured using a modification to a COTS part for our defense customer using 18-8 stainless steel material with standard 2-56 3A thread and standard socket head dimensions.  Length underneath the head was designed to .750″ +/- .005″ and the shoulder was turned to a diameter of .052-.054″, at a length of .066″ +/- .005″.  The thread had to be chased for each part to ensure smooth thread transitions after the additional shoulder was incorporated.