I've had it for years, it's called XmtoGo, i don't think they make it any more.

MD - If you're going to keep the car for a long time, it might be more economical to buy the lifetime subscription for that radio, but check to see if it's transferable if the car is totaled or sold, I think they let you transfer it to the new car if it has an XM radio in it. Or, as I suggested, get a portable and a lifetime sub, and move it between cars.

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