This is pulse module, can provide 2.5 KHZ-68 KHZ frequency, supply signal to stepper driver. If you want to control the stepper motor, you still must use a motor driver. If you want to change the frequency range, you can change C46 capacitance. Power supply: DC15-80V or DC 12V. Motor reversing and the rotation, stop and run can be controller by keys. Motor speed can be controlled by adjusting the potentiometer Colour:green Material:plastic Size:about 73 x 51 x 37MM Package Contents: 1 * Stepper motor Pulse Signal Generator module driver controller Speed Regulator Only the above package content, other products are not included. Note: Light shooting 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.