Used AM-FM-Sat radio + 6 CD player.
This is part of the JBL Prius sound system. To fully use you would probably have to also have the JBL amplifier that is under the front passenger seat and you would also want to upgrade the speakers. For the Satellite radio you would also need it's antenna.

The 6 CD player is a bolt on the top unit above the radio and can probably be used with a regular AM/FM radio but I have not tried it.

We also include a write up about cleaning the piston rings.  This prevents catalytic converter failure due to oil burn and keeps the engine cleaner for longer life. (The next to last picture shows a piston at the beginning and end of a soak. and the last picture show the same piston after 300 miles. It looks different because it is closer to the top of the cylinder.)