Mcoplus BG-D3100 Vertical Battery Grip Holder Pack for Nikon D3100 D3200 Digital SLR Camera Use EN-EL14 Batteries Multi-Power DSLR Vertical Battery Grip for Nikon D3100 D3200 Hold 2 EN-EL14 Li-ion batteriesprovide approximately twice the shooting capacity of the camera (batteries not included). With the vertical shutter-release button,allow half-press focus of the vertical shutter. Especially suitable for shooting in a large quantity or low temperatures environment. Combines the functions of a high-capacity battery pack with a vertical grip.