The Canon Battery Grip BG-E6 is an optional battery
grip designed specifically for the Canon EOS 5D Mark II. It allows
users to load a choice of one or two LP-E6 battery packs. 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 camera's movie mode or Live View mode -
operating modes that use more power. In addition, with the included
BGM-E6 Battery Magazine, you can alternatively also run the camera off
six AA batteries.
Furthermore the BG-E6 provides full vertical
shooting controls, which can be independently turned on or off as the
photographer needs to enhance camera handling, especially for shooting
vertical pictures.
