We Are Rewind Portable Bluetooth Cassette Player(Re)discover all the pleasure of analog sound with our modernized cassette players: Serge, Keith and Kurt. Like the old school cassette players, our players have fast forward rewind buttons, a headphone output, a volume control and an audio input so you can create your own mixtapes. But because you have to keep up with the times, we've added a few modern touches First, we've replaced the batteries with a rechargeable lithium battery that provides up