... ,low power consumption 2.High microstep,high torque 3.broad voltae range 4.wide output ... DIR +,DIR-:Stepping motor direction input, voltage level touched off,high towards, low reverse7,ENA+,ENA-: motor free .NOTE:1 ... When ambient temperature is high or working current over 2.7A, fix the module on big metal shell , or use axle ... dimension Stepping motor driver,1.3A-4.5A,high quality and reasonable price