The nikon mb d12 is an ergonomically designed battery grip for the nikon d800 d800e and d810 dslr cameras the grip allows you to attach additional batteries for more power and extended shooting times increases max frame rate to 6 fps the mb d12 is supplied with two battery trays one that offers space for an en el15 rechargeable battery and one that holds 8 aa batteries batteries not included the mb d12 battery grip also offers extra stability and includes an alternative shutter release