The EG-E6 Battery Grip is
Dedicated strictly to the EOS 5D
Mark II, and permits one or two LP-E6 battery packs to be installed. With
two packs, the battery life is doubled, compared to using a single LP-E6
pack in-camera. Especially for extended use of the EOS 5D Mark IIís movie
mode or Live View, the BG-E6 is an outstanding accessory. The BG-E6 provides
full vertical shooting controls, which can be independently turned on or off
as the photographer desires.