The Bower wireless Canon C3 shutter release set is an extended range wireless shutter release system designed for users of the Canon EOS 10D, 20D, 30D, 40D, 50D, 5D, 5D Mark II, 5D Mark III, 7D, 1D, 1Ds, 1Ds Mark1, 1DS Mark II, 1Ds Mark III, and 1Ds Mark IV DSLRs. 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.