Features: Made of high quality electronic components, it is solid, durable and good performance, long service life. This controller controls the speed of a DC motor by using a Pulse Width Modulated (PWM) DC voltage with a duty cycle. It can provide a continuous current of 8A to your DC motor or other DC load. Adopting a 10A fuse, it also has reverse connection of power supply and over voltage protections, safe to use. The duty cycle can be adjusted from 10%-100%, wide range. External rotary switches for easily adjustment. High efficiency and low noise. Motor speed controller only, other accessories demo in the picture is not included Specification: Material: Electronic Components Input Voltage: DC12-40V Control Power: 0.01-400W Current: Rated current: 8A, Max. 10A; Static current: 0.02A (Standby mode) PWM Frequency: 13KHz PWM Pulse Width Regulation Range: 10-100% Size: app.6 x 5.5 x 2.8cm/2.36 x 2.17 x 1.1in Color: Green Quantity: 1 Pc Cautions and Instructions: The input of the DC motor regulator should be DC voltage. Do not directly connect the AC voltage, otherwise it will be burn out. The positive and negative terminals of the DC power supply should not be connected reversely, otherwise the regulator will be damaged. The motor is neither positive nor negative.. When the running direction is not consistent with the expectation, the direction can be changed by adjusting the wire sequence. The knob can change the regulator's output duty cycle, thereby changing the motor speed. Note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package includes: 1 x PWM DC Motor Speed Controller