Now you can play tunes from your iPod or other portable audio device through any FM stereo receiver. Just find an available frequency. We add a great convenience feature with TuneCast II's unique Auto toggle which frees you from having to manually switch the unit ON and OFF. It simply powers on when an audio signal is detected. If no signal is detected for a period of 60 seconds, your TuneCast II switches off. This innovation preserves battery life while making your outstanding mobile audio experience easier to enjoy.TuneCast II also features four programmable memory slots allowing you to save the clearest station wherever you go.Features include:Transmits on FM channels 88.1MHz-107.9MHzMemorizes up to 4 FM frequencies Powers on and off automatically Low-battery LED indicator Includes 2 "AAA" batteries so you can play your music anywhere Operating Range: 10-30 ft. (a distance of 10 ft. or less will minimize interference and provide the strongest signal) Audio Frequency Range: 50Hz to 15kHz Includes retail packagingDoes not include iPod, iPhone, or MP3 player