This is a simple dual H-Bridge chip on a carrier board that plugs directly into the Brainstem Moto 1.0 board for stepper motor control. A Moto can accept one or two of these and each H-Bridge board drives a single bi-polar stepper motor. This chip has header pins to plug into the Moto, but no others as you can typically solder both the power and stepper wires directly to the board.