1. new and high quality.Suitable for Genius Pro or SW-X2 or Hornet 3D printer used. 2. Ultra-quiet operation, good heat dissipation,Low-speed silent, high-speed anti-shake. 3. Two-color pin header, stable performance.Large area heat dissipation, lower temperature. 4. The driver is equipped with a heat sink to assist the driver to dissipate heat and increase the heat dissipation area. 5. The heat of the driver chip can be quickly discharged through the heat sink, which greatly reduces the temperature of the driver during operation, which is beneficial to the normal operation of the printer and prevents steps and stops working. Drive capability up to 2.5A Step or Dir interface with microstep interpolation (up to 256 microsteps) Motor voltage:4.75V-32V Logic voltage: 3.3V and 5V Precautions for use: 1. Please pay special attention to direction, do not insert it backwards! 2. When measuring voltage, be sure not to connect the motor, otherwise it is easy to burn . 3. When measuring the voltage, the power should be turned on. Don't just connect the USB powered by. 4. Before adjusting the knob, it must be done with the power off. After the adjustment is completed, perform a power-on test to prevent the driver or the motherboard from burning out. 5. When attaching the heat sink, please pay attention to the distance between the heat sink and the pins, otherwise it cause a short circuit between the heat sink and the pins. 6. When is working, please do a good job of heat dissipation (heat sinkandcooling fan) to prevent abnormal operation of due to overheating. Due to different batches, there may be differences in product appearance and printed text, which not affect use. Colour:As Shown Material:PCBandMetal Package Contents: 4 x Stepper Driver Only the above package content, other products are not included. Note: Light reflection 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.