Relive the good old days with this retro cassette player! [Bluetooth Portable Cassette Player] Play your cassette collection and travel back in time. Tip: Press the \"DIR\" button to automatically flip the cassette. If the play button won't depress, it may be stuck or (FF/REW/STOP) hasn't been reset. [Bluetooth 5.0] Enjoy wider coverage, 2x faster speed, 4x longer distance, lower energy consumption, broader compatibility, and smoother connection compared to Bluetooth 4.2. Note: (Old tapes may have demagnetization, poor sound, noise, and buzzing during playback. If you can't connect to Bluetooth, check if the device is in Bluetooth mode. [Bluetooth Receiver & Transmitter] Bluetooth Output: Stream music to other Bluetooth receivers like headphones or speakers. Bluetooth Input: Connect directly to your phone's Bluetooth. If there's a buzzing sound when pairing, it may be due to interference between the tape device and the Bluetooth signal. Keep the speaker away from the tape device. [3.5mm Interface & FM Radio Function] Compatible with all 3.5mm interface devices like speakers, headphones, and car stereo speakers. FM mode can receive radio (using 3.5mm headphones as an antenna) and supports automatic FM channel search. The radio function will be a great companion for your life and leisure. [2 Power Supply Options & Auto Reverse] The wireless cassette player is powered by 2 x AA batteries (not included) or a DC 5V power supply (not included). With auto-reverse, you can choose to listen to music on one side or both sides depending on your preference. This stereo cassette player fits perfectly in your pocket for travel.