1[Bluetooth Portable Cassette Player] Play your tape collection, this retro cassette player allows you to travel back in time and relive the good memories of the past. Tip: Press the "DIR" button to auto reverse the cassette. If the play button cannot be pressed down, which may be caused by the key being stuck or (FF/REW/STOP) not being reset. 2[Bluetooth 0] Compared with Bluetooth 2, 0 has wider coverage, 2 times speed, 4 times distance, lower power consumption, wider compatibility, smoother connection. Note: (If the tape is old, there will be degaussing, poor sound, noise and hum during playback. If you can't connect to Bluetooth, please check if the device has Bluetooth mode. 3[Bluetooth Receiver and Transmitter] Bluetooth Output: Transfer music to other Bluetooth receivers such as headphone or speaker. Bluetooth Input: Directly connect with phone Bluetooth. If there is a buzzing sound when pairing, it may be caused by interference between the tape drive and the Bluetooth signal. Keep the speaker away from the tape drive. 4[5mm Interface and FM Radio Function] Accepts all 5mm interface devices such as speakers, headphones, car stereo speakers. FM mode can receive radio (with 5mm headphones as antenna) and supports automatic FM channel search function. The radio function will be a good companion for your life and leisure. 5[2 Power Ways and Auto Reverse] The wireless cassette player is powered by 2 x AA batteries (not included) or using DC 5V power supply (not included). With auto reverse, you can choose to listen to music on one side or both sides according to your preferences. The stereo cassette player fits perfectly in your pocket to travel.