The Green Extreme Professional Power Battery Grip for the Canon 5D Mark 4 is an optional but essential accessory with excellent ergonomics designed specifically for the Canon EOS 5D Mark 4. Featuring intelligent links to camera functions, matching the design and feel of your camera while doubling the battery power with a twin cell chamber that can load a choice of one or two battery packs. This is especially useful when taking advantage of the camera's Movie Mode or Live View mode - operating modes that use more power compared to using a single LP-E6N pack. The non-slip rubberized grip offers perfect balance in any direction with 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 - not videos, please. The grip has generous operating controls as well: shutter button, Main Dial, multi-controller, AF point selection button, AE lock/FE lock button, AF start button, and multi-function button. The base of the grip has a standard 1/4-20 tripod socket and a hand strap mount. Your camera's original battery door fits snugly in a protective hidden slot for instant retrieval. Get a grip.