Precise Speed Control: Our motor speed controllers control the speed of DC motors by adjusting pulse width modulation (PWM), provide accurate and adjustable speed control for a variety of motors and help you achieve the speed for your specific purpose..It has an LED display; a potentiometer knob and a front brake-reverse switch. Widely used: The adjustable voltage range is truly smooth and can be adjusted from 10V to 55V.The DC motor driver can brush motor speed and dimming adjustments in the DC circuit.Note: Electric vehicles cannot be used. Material: The motor speed controller is placed safely in a sturdy aluminum box, and protects it from injury.Additionally, the holes on the sides and top of help it stay cool and it runs well. Input voltage: DC 10-55V; Output voltage: linearity under load; Input current: 60A; Rated current: 40A; Speed range: 0- ; Speed type: Regulating current; PWM frequency: 15KHZ; Potentiometer:Linear; Wiring type: Terminal; Colour:As Shown Material:Metal Package Contents: 1pcs x pwm controller Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.