The AVX system uses rechargeable batteries (4 hour life on receiver; 15 hour life on body pack transmitter,) that recharge via the universal micro usb cable found on many cell phone chargers. The mics can also run continuously if powered by the micro usb.
The receiver is a unique cable-less design that plugs directly into an xlr port on your camera. It comes with a cable adapter if you need to use it on your dslr with a 3.5mm plug.
The expected range is around 30 meters for the mics. They operate on the 1.9ghz frequency range, where baby monitors and the like operate. No license is needed. The digital system means the receiver and transmitter pair together automatically without having to worry about what frequency they’re on. They’ll automatically jump to new frequencies if it senses interference, and they claim there will be no effect on the audio.