The Vivitar Battery Grip for the Sony A7/A7R camera holds 2 NP-FW50 batteries (not included), providing twice the power of a standard battery pack. It also includes a wireless IR remote and receiver that allows you to take pictures within 20 feet. Additionally, this Power Grip provides a vertical shutter release button. This option makes shooting with the camera in a vertical position just as comfortable as shooting horizontally. The Power Grip securely attaches via the tripod mount on the bottom of the camera.