Offering two Nikon EN-EL15 battery slots, and 1/4 -20 mounting threads on the sides, this power system for Sony A7S/A7RII Camera allows you to provide extended power to your Sony A7 Camera. It features a 2.5mm DC output jack that lets you connect out to a 7.2V device using an appropriate cable. Two 1/4?-20 threads, one on each of two sides, allow you to use rod clamps and shoe mounts for mounting. Slightly more compact than its Quad relative, this power system can conveniently be used camera-top, attached between a camera and monitor.?Only one battery is required to be used at a time, so you can hot-swap batteries. An LED indicator remains lit as long as sufficient power is available. Made in the USA.