R-TECH 780389 Control Knob Button for PCB Mount Switches with Tran...

R-TECH 8.4mm x 9mm Control Knobs for PCB Switches - R-TECH 780389, A transparent R-TECH control knob / button, compatible with PCB mounting push button switches with 3.3mm square shafts. R-TECH 780389 Control Knob Button for PCB Mount Switches with Transparent Finish

Price: 0.40 from Rapid Online Rapid Electronics Ltd.