Arduin Kit - 3D Printer Kit , 1pcs Mega 2560 R3 + 1pcs RAMPS 1.4 Controller + 5pcs A4988 Stepper Driver Module /RAMPS 1.4 2004 LCD Control A simple steps and direction control interface Can interface directly with 3.3 V and 5 V systems Over-temperature thermal shutdown, overcurrent shutdown, undervoltage lockout Adjustable current control lets you set a potentiometer, which lets you use the stepper motor\'s rated voltage or more, in order to achieve a higher rate of maximum output current step Intelligent chopping control automatically selects the correct current decay mode (fast decay or slow decay)