16 Channel PWM Servo Motor Driver Controller Board Module Bluetooth PCB steering gear for SG90 MG995 Arduino Robot Raspberry Pi DIY Servo Shield Module 16-way steering gear control USB / TTL connection Speed adjustable, Isolated drive, Stable performance, never burn board USB power supply(for writing program), no need to install drivers. Just define the state, no need to to calculate detail of the action Two-way power supply for the control board and steering gear, arduino, robots, raspberry pi, motors and other equipment