iSunnao Bluetooth Car Kit Music Audio Receiver

How is it powered?

According to the product page at the mothership ( it has a battery. One of the reviews mentions that it has a microUSB slot for charging.
Battery lifetime up to 8 hours.

How is the interference with these?

I like the idea. The cigarette lighter models too, but keep reading about how the transmission causes nasties.

will allow you to make hands free calls using bluetooth?