Specifications:Model: KM-1Operating voltage: DC 6-12VPCB board size: 40 x 40mmCircuit description:KM-1 uses PWM (pulse width modulation) to control the speed of the motor, adjust the pulse width duty ratio, so that the speed from zero to the maximum speed stepless speed regulation. The wider the crest width of the control waveform, the faster the motor speed; on the contrary, the wider the width of the control wave trough, the slower the motor speed.Circuit boards and components are made of high quality devices to ensure the success rate and stability of the circuit.1. The circuit board is made of high quality material, the welding pad can endure many times welding and won't fall off;2. Speed potentiometer using sealed potentiometer with long service life, not easy to enter the dust, not easy to oxidation and so on;3. Motor performance stability, small noise, large torque.Package included:3 x KM-1 DC 6-12V PWM motor speed controller kit