Yes, the CoolStream Duo will work with the Aux port in your car to stream music to your car or motorcycle stereo speakers. If your AUX-IN is next to a power source like a USB port or cigarette lighter, as shown here, you can keep the Duo charged as well.

The Duo will NOT stream music using just the USB port. This only provides power to the Duo’s battery. It does NOT connect to the stereo.
The CoolStream Duo has a rechargeable battery. Once charged, you can use the Duo plugged into the AUX port running on battery power. 1-2 hours of charging provides 4-5 hours of streaming.


To use the Duo on battery power, turn on the battery by moving the top button to the left. Now pair your phone to the Duo. Select music from your phone to stream music to your Car Stereo speakers.
We include a dual-tipped 3.5 mm cable with every Duo so you can use the Duo with any vehicle or motorcycle that has an Aux port. As long as you can charge it, you can use it. While it is charging, you will see a red light flashing. When the red light goes out, your Duo is ready to stream. You can then expect between 4 and 5 hours of streaming capacity.


If you want to keep the Duo fully charged all the time so that it is available for streaming, you can always use an iPod charging cable while it is in your vehicle.
You could use either a cigarette lighter to 30-pin charger or a USB to 30-pin charger to keep your Duo fully charged. The Duo will NOT work for music streaming using only the USB to 30-pin. This is for providing power to the Duo only. You MUST have an Aux port to connect to the stereo.