The Precision BG-C4 is a battery grip designed for use specifically with the Canon EOS 7D digital SLR camera. It accepts up to 2 LP-E6 batteries to effectively double the camera's battery life. The included AA battery holder allows you to use 6 AA batteries for added convenience. The BG-C4 offers an alternate shutter release button, AF start button, AF point selection, AE lock/FE lock button, multi function button, and main dial to facilitate shooting in a vertical orientation.