The MB-D15 Multi-Power Battery Pack for D7100 & D7200 from Precision is a battery grip designed for use specifically with the Nikon D7100 & D7200 digital SLR camera, and accepts one EN-EL15 battery. With one battery in the MB-D15 and one in the D7100 & D7200, your shooting time is effectively doubled. Moreover, when one battery is drained, it can be removed and recharged while you continue shooting with the other battery. In addition, the MB-D15 can utilize 6 AA batteries and comes with the MS-D14 AA Battery Holder that slides into the battery grip. The design of a battery grip offers a comfortable and secure way in which to hold your DSLR, especially in the vertical position. And the MB-D15 features an alternate shutter release button, AE/AF lock button, multi-selector, and dual command dials to facilitate shooting when held vertically. The MB-D15 is constructed with anti-slip rubber grip to further improve handling, a tripod socket to mount your camera directly to a tripod and employs magnesium alloy equivalent to that in the D7100 & D7200 body to achieve superior dust-prevention and weather-resistant performance.