3.18mm post length is recommended for PCB thickness of 1.58 to 2.36mm max. AMPLIMITE HD-20 Series, All-Plastic, PCB Mount D-Sub Connectors. AMPLIMITE HD-20 All-Plastic series straight posted PCB mount d-sub connectors with 94V-0 black thermoplastic housings pre-loaded with size 20 DF posted pin contacts gold plated. These HD-20 All-Plastic PCB board mount d-sub connectors have 3.18mm posts and either 3.05mm mounting holes, threaded inserts orfixed female screwlocks. For suitable screwlocks where required see stock numbers ; 717-4470 717-4470 and ; 680-9351 680-9351 typically.