The Canon 7D Battery Grip BG-E7 is an optional battery grip designed specifically for the Canon EOS 7D. It allows users to load a choice of one or two LP-E6 battery packs (not included). With two packs, the already impressive battery life is doubled, compared to using a single LP-E6 pack in-camera. This is especially useful when taking advantage of the cameras movie mode or Live View mode operating modes that use more power. In addition, with the included battery magazine you can alternatively also power the camera off six AA batteries.