This FM Transmitter is capable of delivering power via USB.
The iCarPlay 300 does not require external power to transmit, but also does not charge your MP3 player while it is in use without being hooked up via USB to an external power source. The iCarPlay 1000 cigarette adapter has a USB port which powers both the transmitter and charges your battery while the unit is plugged in. The transmitter can be detached from the power piece and other, allowing you to use the cigarette adapter with other USB-powered equipment.