Wireless RF (radio frequency) remote control features maximum operating range 100m. Compared to an infrared (IR) remote control, it allows you to operate the shutter from either direction / angle. It supports unique coding for anti-interference and avoiding wrong operation. 3 operations modes: At W mode, the receiver is active, you can use the transmitter to control the shutter or focus. At O mode, the receiver will be a normal remote switch, and it will not consume any power. At L mode, the receiver will lock the shutter for long exposure.