D-Sub Board Lock Screw for FVS/FCT Connectors
The Molex 1731120333 is a slotted board lock screw from the FVS and FCT series, designed for use with standard D-Sub connectors. It carries a 4-40 UNC thread — the industry-standard jack-screw size for D-subminiature connectors — and a nickel-plated steel finish for corrosion resistance in industrial environments. The screw provides 0.610" (15.50mm) of thread length below the head, with 0.177" (4.50mm) of that being the threaded engagement portion that mates into the connector's threaded insert.
Thread Fit and Panel Compatibility
The 4-40 UNC thread mates with the standard threaded insert found on D-sub backshells, hoods, and receptacle connectors. The 0.610" (15.50mm) total length below the head accommodates panel thicknesses up to roughly 0.433" (11.00mm) before the threaded portion bottoms out — the 0.177" (4.50mm) threaded section is what actually engages the mating thread. For thinner panels, the slotted head allows a screwdriver to cinch the connector pair tight without over-torquing the plastic housing.