The Bower RCWS1R Wireless Shutter Release Set is an extended range wireless system designed for professional and advanced amateur users of select Sony and Minolta cameras. The set consist of the receiver and the shutter release transmitter. The remote system is very handy for taking pictures of subjects that are difficult to approach, or to minimize vibration for close-ups and time exposure. The remote fires the camera from a maximum distance of 90'. Sixteen transmission channels are available to prevent interference between other cameras using wireless remotes.