8 Position Rotary Switches can be used to control various ECU functions such as Traction Control and Boost Control settings. Installation is simple, just connect 5V supply, sensor ground, and the output signal. Rotary switches can be connected to any unused analog input on the EMU, EMU Black, or PMU16. Dimensions:Mounting hole size: 8.8mm to 9mm (8.8mm thread OD)Locating tang for fixed mounting position: 3mm (W) x 0.60mm (Thick)Locating tang distance from center of mounting hole: ~8mmBoard measurement: 22.75mm x 21.15mmDepth from mounting location to back of board: 12mm (including clearance for solder legs)Knob: 16mm (L) x 15mm (OD)Total from solder legs on rear of board to top of knob: ~32mm Downloads:Seesection 39 \”Tuning EMU Boost Control and Configuring ECUMaster 8-position Rotary Knob\” in the FAQ and TROUBLESHOOTING DOCUMENTlink on our Downloads page.