1803BK DC Motor Speed Regulator controls the speed of a DC motor by adjusting Pulse-Width-Modulated (PWM). The input power range is DC 1.8-15V . Use a 2A resettable fuse to protect the controller. Potentiometer with switch function. Operating instruction: Before you attempting to wire the controller, make sure power is off. WARNING: TO CHANGE MOTOR DIRECTION, INTERCHANGE THE POSITIVE AND NEGATIVE WIRES OF MOTOR. Connect wires refer to the "wiring diagram" (NO.5 picture). Turn on the power, and adjust the potentiometer. The LED indicates the power up and the speed of motor. Input supply voltage: 1.8V-15VDC; The maximum output power: 30W The maximum continuous output current: 2A Duty Cycle adjustable: 0%- Material: Plastic Colour: Green Item size: 1.3 x 1.3 x 0.6 inches; Net Weight: 0.5 ounces Package Contents: 1 x DC Motor Speed Controller Only the above package content, other products are not included. Note: Light 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.