This Power System for Panasonic YAGH Interface powers an optional interface unit using two available Canon LP-E6 type batteries. The unit requires two batteries to supply enough power, running the batteries in series to provide sufficient power to run the audio interface. Attach two batteries to the unit, and insert the 4-pin XLR connector into the YAGH. An integrated blue LED lights up when you have sufficient power. The 30″ long cable allows you flexibility in mounting the battery system to your tripod or rod support system. Made in the USA.