BestDealUSA Pro Camera Battery Grip Pack for SONY Alpha SLT A77 A77V as VG-C77AM This is a professional vertical battery grip for Sony Alpha DSLR- A77 / A77V, compatible with original Sony VG-C77AM,that can hold one or two NP-FM500H. Batteries. It can double the battery capacity of your camera,It allows users to add a vertical shutter release for more comfortable portrait shooting. Effectively doubles your shooting time. Dramatically improves stability. Suitable for:Sony Alpha DSLR- A77 / A77V Compatible With: Sony VG-C77AM