Wurth WA-SMSR Series SMT Reverse Steel Spacers with Through Hole WA-SMSR series PCB SMT reverse spacers made from tin plated steel with a 3.2 mm diameter through hole. These SMT spacers are soldered on the top to create spacing on the bottom of the PCB. The spacers are suitable for automated assembly and offer a high tightening torque and mechanical strength. When used on a standard PCB thickness of 1.6 mm these SMT spacers can be used to create distances from 1 mm to 10 mm