Yescom Variable Fan/Router Speed Controller 3 Settings Hydroponics Inline Fan Exhaust Air 500W to 1800W Adjuster Fan/blower speed controller with 31 1/2" grounded power cord, applicable for fan or router which power is from 500w to 1800w Fuse protected; UL listed power cord and plug for safe use; Lightweight, practical and easy to use One control switch for 3 settings: Variable Speed, OFF and Full Speed; Speed control dial to control variable speed: Low, Medium or High speed With built-in grounded control outlet and metal clamp at the back; Perfect for controlling speed of high velocity inline fan and mini blower Note: The Fan Speed Controller is NOT compatible with brushless type motors. Please only use it with FANS that have a universal brush type motor.