The Ryobi Electric Tools 039858011099 Fan Speed Switch & Circuit Board Assembly helps restore proper fan speed control and electrical operation in compatible equipment. This replacement assembly combines a speed switch and circuit board to regulate fan operation. It works by controlling electrical signals and power delivery, allowing the fan to operate at the selected speed. Suitable ... https://www.wholetoolbox.com/ryobi-electric-tools-039858011099-fan-speed-switch-circuit-board-assembly/039858011099.html