Using as wireless audio transmitter, plugged into a mixer/amp on my motorcycle, which in turn, carries the audio from devices plugged into it-- radar detector, xm sat radio, gps, MP4,iPod etc. using a sony BT receiver with built in FM radio and earplug speakers under my helmet. This allows selective listening with all devices that have no Bluetooth function. Good features 1.Because it carries it's own charge it doesn't drain the batteries of device. 2 It's very small, won't take too much place. 3. You control the sound volume from the device. 4. It uses a standard micro usb port to charge so I can use my callpod charger and my motorola charger. 5. It sounds really clear. 6. Listening music from iPod without wires, freely, i can do my own thing. 7. For the price- well worth it. Convenience of no wires connecting me to the bike is also a way to minimize distracting wires getting hung up while riding or when dismounting. Overall, it's very useful and convenient. Really like it.