The Nikon MB-D200 Multi-Power Battery Pack holds two EN-EL3e Lithium-Ion rechargeable batteries, effectively doubling your total shooting time or holds the MS-D200 AA Battery Holder (included) so users can use AA batteries as a power backup. The pack also provides an AF-on button, vertical firing release with lock and front and rear command dials. Requires one or two EN-EL3e or six AA batteries (not included).