Description: Working voltage: DC 10v-35v. Recommended to use a switching power supply dc 24v rated maximum output: A± 3a, peak 3.5a. Using the Toshiba tb6560ahq chip with low voltage shutdown, overheating stop and over current protection circuit to ensure optimal performance for two-phase within 42,57 stepping 3a / four-phase / of line four / six-wire stepper motor, and is not suitable for more than 3a stepper motor. Automatic half current function 6n137 high-speed optical coupling, ensures high speed without losing step. Subdivision: Whole step, half-step, step 1/8, 1/16 step, a maximum of 16 subdivisions. Size: Approx. 75x50x35mm / 2.95x1.96x1.37inch features: Current grade-by-adjustable to meet your demand for a variety of applications. Semi-automatic flow adjustable 6n137 high-speed optical coupling, ensures high speed without losing step plate printed setup instructions operation without manual also thick teeth radiator, good heat dissipation package includes: 1x stepper motor driver.