Kastar Professional Vertical Battery Grip (Replacement for VG-C77AM) for Sony SLT-A77 SLT-A77V SLT-A77 II Digital SLR Cameras Kastar Pro Multi-Power Vertical Battery Grip same functions as the original battery grip Sony VG-C77AM Hold 2 NP-FM500H Li-ion batteries, doubling the battery capacity of your camera, effectively extending your shooting time. When using two batteries, the grip will automatically switch to the second battery if the first becomes depleted. Switching does not interrupt camera operation. Professional edition with vertical-grip shutter-release button, main dial, AE-L button, Index/Reduce button and Exposure button. Vertical shutter with half-press function, more comfortable vertical shooting. High quality product and Manufacture price, include 30-day Money Back and one year Warranty.