FC-210C is the professional Transceiver that can remote control different group flashguns and achieve TTL communication between the TTL flashgun and camera, at the same time synchronized flashing the Off-camera flashgun.FC-210C also is a trigger for single controlling off-camera flashgun synchronized flashing, controls Off-camera flashgun groups synchronized flashing, and remote controls shooting.FC-210C is adopted with worldwise free FSK 2.4GHz wireless frequency, which guarantees speed, distance, and stability. Its remote control distance range is about 100meters in an open area.