The Speed is electronic with sole to an motor's just those your and fans. router controller with universal brush-type The features 3 way switch high, or options. If used with fan and filter for ventilation, the suitable and adjustable fan speed is good for utilizing your carbon filter more efficiently.
One control switch for 3 settings: Variable Speed, OFF, and Full Speed
Variable speed: Low, Medium or High speed
a metal clamp at the back of the speed controller
2 years warranty any issue contact customer service with order ID