This MKS CD V1.0 stepper driver breakout board is used when stand alone stepper driver is used with a board which is designed for small stepper drivers (A4988 & DRV8825). So if you have a RAMPS 1.4 board and need to drive a stand alone stepper driver (like the TMC2160-OC stepper driver), then this board will give you easy access to the signals needed for the stand alone stepper driver.