The Jupiter is a small transmitter, powered by a watch battery, that transmits your cell phone conversation through your radio speakers. You simply plug the Jupiter Jack into the cell phones headset input (numerous adapters are supplied) and tune your radio to 99.3FM. An alternative frequency is available should 99.3 be busy in your area.

The only issue I encountered was that the supplied phone holder hit the phone's volume button on the side of the phone which turned off the ringer and made it difficult for me to be heard. Once this was realized, and with just a little trial and error, the device worked fine.

I also communicated with the Chicago Police Department and learned that although there is a law against driving while using a cell phone in the city, it is permissable to use the phone with a "handsFree" device.