Features: Made with high quality circuit board which ensures a longer service life. Equipped with fuse tube to protect the speed controller from burning out that short circuit causes. Controls the speed of a DC motor with this controller High efficiency, high torque and low heat generation. With reverse polarity protection, high current protection Operating. Adjusting the potentiometer knob changes the governor output duty cycle and the motor speed changes. Specification: Item Type: PWM Motor Speed Control Switch Material: Electronic Components Output current: 0-5A Output power: 90W (maximum) Quiescent current: 7uA (standby state) PWM duty cycle: 1%-100% PWM frequency: 20khz Weight: Approx. 16g Package list: 1 x Motor Speed Controller Switch Notes: Do not reverse the positive and negative terminals of the DC power supply, otherwise the governor may be damaged. The motor can be positive or negative. When the running direction is inconsistent with the expectation, the direction can be changed by adjusting the line sequence. Adjusting the potentiometer knob changes the governor output duty cycle and the motor speed changes..