The Hahnel HN-D7100 Infrapro Battery Grip for Nikon D7100 Cameras is an easy way to double your shooting time and get a better grip while shooting in portrait orientation. This professional battery grip operates on 1 or 2 rechargeable EN-EL15 or HL-EL15 lithium-ion batteries or 6 rechargeable Ni-MH or alkaline AA batteries for much longer shooting sessions, without having to stop to change or replace batteries. The grip attaches securely to the camera body and there's a vertical firing release with a lock, so shooting verticals is as easy as shooting horizontals. It can also use the optional EP-5B Power Supply Connector for continuous power.