Check the listing for details. Rotovac Controller Board, Speed Controller, Dimmer Switch Aftermarket2. Condition: New. Listed at 175.00 USD. You get a controller board, speed controller, dimmer switch , on off switch to adjust the speed high and low. Also used as a switch on and off All the wiring is soldered on and attached. Do not unplug wiring and plug it back in unless necessary for a good connection in the future, they can get loose. the controller board heat sink is larger so you need to drill a new hole under the rotovac decal like in the picture. drill bit included. Comes with soft start feature, which means it doesn't turn on full speed right away, it slowly ramps up to the speed set on the dial to extend the motors life make it last longer The way to test a controller board is to remove the wiring from the electric motor and run it off of your car battery. Take jumper cables that are hooked up to your car, and hook the motor on the rotovac 360i up to the jumper cables. If the motor spins slowly the motor is good and the controller board dimmer switch, or the wiring is bad. This motor will run off a car battery but very slowly, just for testing