This Vivitar Battery Grip is specially designed for use with the Sony A9/A7RIII/A7MIII Cameras. It uses two NP-FZ100 batteries (not included) which provides the power to shoot up to 800 pictures. Mounted on the bottom of the camera, the grip sports a vertical shutter button just perfect for portrait photography and includes an AE/AF lock button and zoom control for consistently great shots.