Eliminates the need for a cable release. Allows the camera to be fired from a
distance up to 100 ft. uses RF (radio frequency) signals, not line-of-sight like
infrared. Designed to fit specific cameras. Transmitter has a 2 position
switch…press lightly for prefocusing, and then continue pressing to release
the shutter. LED lights indicate prefocus and exposure. May be used on up
to 16 channels…user settable.