Thread Size and Dimensional Fit
The 177619-1: The 4-40 thread (both socket and screw) is the standard UNC jacking screw size for D-sub connectors in the AMPLIMITE HD line. The threaded portion below the head measures 0.138" (3.51 mm) — enough to engage the mating screwlock on the receptacle side without bottoming out in a standard panel thickness. The total length below head of 0.197" (5.00 mm) includes the spring washer. If your panel or PCB thickness exceeds 0.197", this jackscrew will not protrude far enough to engage the mating half; you would need the longer-thread variant from the same series.
Compatibility and Series Match
The 177619-1 is listed for use with AMPLIMITE Series HD connectors. This is the high-density variant of the AMPLIMITE D-sub family — the contact spacing is tighter than standard AMPLIMITE, and the shell dimensions differ slightly. The jackscrew itself is mechanically interchangeable with other 4-40 D-sub screwlocks, but the spring washer preload and the threaded insert profile are tuned to the HD shell. If you are retrofitting a standard AMPLIMITE D-sub, verify that the 4-40 socket clears the shell cutout without interference.