Phottix Battery Grip D3200 (with vertical button) - For D310
Finally: A battery grip for use with Nikon D3100 and D3200 DSLR. This grip takes one or two EN-EL14 batteries. Effectively double your shooting time and make a small camera body easier to hold. This grip comes with a shutter-release button to make vertical shooting easy and comfortable . A short cable connects the battery grip to the Nikon D3100, D3200's remote port to provide this functionality.