Comfort and Control in Vertical Position. Vertical Position Shutter Release Button .Vertical Position Control Buttons & Dial.Extends Shooting Time . is an optional battery grip with improved ergonomics designed specifically for the Canon EOS 5D Mark III, 5DS, and 5DS R. 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.