The Green Extreme Professional Power Battery Grip for the Canon EOS 6D DSLR Camera is an optional but essential accessory with excellent ergonomics, designed specifically for the Canon EOS 6D DSLR. It all starts with intelligent links to camera functions. The grip matches 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 - selections that put more demand for power on your batteries. Your uptime will besignificantly better compared to using a single LP-E6 pack. In addition, with the included battery magazine, you can also run the camera off six AA batteries. 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 thegrip 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.