This Multi-Power Battery Grip allows the Nikon D300 & D700 to powered by two EN-EL3e batteries simultaneously - one in the camera body and one in the battery grip - effectively doubling your shooting capacity. The performance is equal with the original model MB-D10.
The battery grip also provides a comfortable vertical grip with an additional shutter release and scroll wheel for easy access to the camera functions when shooting in the vertical orientation. It is also fairly compact. In this professional edition, it comes with several functional buttons AE lock/FE lock for easier vertical shooting.
With the included AA battery holder, users can power the camera with 8 AA batteries. Or you can use the Nikon EN-EL4 or EN-EL4A battery combined with the optional Battery Chamber Cover to obtain a higher frame advance rate (8 Frames per second in the D300) than the EN-EL3e battery can provide.