TOOGOO(R) KK2.1 Multirotor LCD Flight Controller Board 6050MPU 644PA Multirotor update version with Protective Case for FPV Multirotor Quadcopter New KK2.1 Multirotor LCD Flight Controller Board 6050MPU 644PA Multirotor update version for FPV Multirotor Quadcopter added polarity protection to the voltage sense header and a fuse protected buzzer outputs The board is clearly labeled and the voltage sense line color has been changed to red for easy identification AVR interface: standard 6 pin. Color: Green