The Phottix Battery Grip BP-550D (BG-E8) is a Premium Series Grip/Battery Holder for Canon EOS 550D / Rebel T2i / 600D / 650D / T3i digital cameras. This battery grip can hold two LP-E8 or six AA batteries. It is equipped with a vertical grip shutter button, main dial, AE lock/FE lock and AF point selection controls for easier vertical shooting. The grip also has a tripod socket.