The 30" Power Converter P-Tap to Sony A7 Type Dummy Battery from IndiPRO Tools allows you to power your camera using external batteries with a P-Tap power connector. The converter regulates any input voltage within the range of 12 to 18 VDC, providing 7.2 volt output. It features a P-Tap connector on one end and a dummy battery that fits into a Sony A7 battery compartment on the other end.