Bluetooth Audio Streaming, 3.5mm Stereo Input, Rolling 2-Hour Recording Loop, Stereo Configuration, 76W of Total Power, Built-In FM Tuner, Antenna in Handle, Up to 72-Hour Rechargeable Battery, Motorized User Interface. Listen loop and rewind audio on-the-go with the ochre Teenage Engineering OB-4 Magic Radio Recorder and Speaker with Bluetooth. Source your audio by streaming via Bluetooth from a mobile device use the smart antenna to dial in FM radio plug in an audio device via the 3.5mm line in jack or access the experimental disk mode. Whatever you play is continuously recorded on a rolling 2-hour loop tape so you can rewind and listen again. Whey playing audio clear and dynamic sound emit from the OB-4's two built-in woofers and tweeters powered by two 38W Class-D amplifiers.