Product OverviewThe Bower wireless Sony S1 shutter release set is an extended range wireless shutter release system designed for users of the Sony Alpha A100, A200, A230, A300, A330, A350, A450, A500, A550, A560, A700, A850, A900, SLT A33, A35, A37, A55, A57, A65, A77, A99, digital cameras. The remote system is handy for taking pictures of subjects that are difficult to approach, or to minimize vibration for close-ups and time exposure. The set includes one receiver and one transmitter that works at nearly any angle. The remote triggers the camera from up to 90 feet (27.43m) and its 16 available transmission channels minimize cross-channel interference between other camera users with wireless remotes.