1. The output current is steplessly adjustable to meet your application needs. 2. Automatic semi-flow function. And it is equipped with an automatic half-flow switch, which is easy to use. 3. 6N137 high-speed optical coupling is used to high-speed without losing step. 4. The subdivision setting instructions are printed on the back of the board. 5. Adopt enlarged radiator for good heat dissipation. With output short circuit protection function, worry-free use. Adopt common anode input mode, there are two input terminals, wiring is more convenient. 1) Working voltage DC 10V-45V. It is recommended to use a switching power supply DC32V for power supply. 2) 6N137 high-speed optical coupling is used to high-speed without losing step. 3) Using 's -current, high-voltage TB6600HG original chip, there are low-voltage shutdown, overheating shutdown and overcurrent protection circuits, and short circuit protection is added compared to TB6560. 4) Rated maximum output: ±4.5A. 5) Suitable for 42, 57, 86 two-phase/four-phase/four-wire/six-wire stepper motors within 4.2A. 6) Automatic half-flow function. 7) Subdivision: full step, half step, 1/4 step, 1/8 step, 1/16 step, big 16 subdivisions. size: 50 x 82 x 35MM Material: PCB colour: green + silver Package Contents: 4 x TB6600 Stepper Motor Driver Board 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.