... the rear-curtain sync function.Compatible with:Compatible camera models: Canon EOS 1100D, 1000D, 600D, 550D, 500D, 450D, 400D, 350D, 300D, ... , 1D Mark III, 1DMark II, Rebel T3i, Rebel T3, Rebel T2i, Rebel T1i, Rebel T, Rebel XSi, Rebel XS, Rebel XTi, Rebel XT, Rebel X, Kiss F, Kiss X50, ... : 24-105mm (16mm with diffuse panel), automatically set for lens focal length;Power source: 4 x AA batteries (Ni-MH ...