DescriptionAdjustable current control lets you set the maximum current output with a potentiometer, which lets you use voltages above your stepper motor's rated voltage toachieve higher step rates.Features- Color: Shown in the pictures. - Material: Electric components. - Size: Approx. 0.7 * 0.7 * 0.7cm/ 0.28 * 0.28 * 0.28 inch(LWH). - A4988 driver board widely used in 3D printers and small CNC machines - Simple step and direction control interface. - Thermal protection, over-current protection, ground fault protection. - Five different step resolutions: full-step, half-step, quarter-step, eighth-step, and sixteenth-step.