The Pioneer MVH-S100UB lets you listen to your digital music collection in the car. You can easily connect an MP3 player, smartphone, or USB flash drive to the USB and AUX port. If you connect an Android phone to the USB port, your device's battery will be automatically charged. This way, you'll never exit the car with a dead phone. If you prefer listening to the radio, you can set up to 24 preferred channels. This way, you can quickly switch between your favorite programs. The car radio features 1 RCA pre output. You can connect an amplifier or subwoofer to it.