The MVH-S215BT lets you enjoy hands-free calling and audio streaming in the car . courtesy of built-in Bluetooth with internal mic. Other entertainment options include a front USB input . Aux-In and AM/FM radio. Receive pristine sound from the MVH-S215BT’s built-in amplifiers with 4 x 50W of pure MOSFET power. For even more power . you can use the RCA pre-out to hook up an amplifier to provide additional power for speakers or subwoofers.