Wirelessly transmit XM to any FM stereo with built-in FM modulator, 30 minute Pause and Replay flash memory for recording programming, Alerts you when a favorite artist or song is playing on another channel, Personalized sports and stock ticker, Channel preview allows you to view songs and artists on other channel, Compatible with all previous SKYFi hardware, 4 11/16 W x 2 15/16 H x 1 1/2 D