Specifications: Model: BT-350 Technology: BT4.1 2.4GHz Operating range: up to 10 m / 33 ft (no barrier) Interface: 3.5mm stereo input jack Mode: support sleep mode, hands-free calling, A2DP stereo Built-in rechargeable battery: 120mAh Charging status: red LED lights up, extinguished when full Working time: 8h Pairing: long press the key for 5 seconds until the red and blue LED lights alternately shine. After the link is successful, it turns blue and flashes slowly. Notes: Some device pairings require a pairing password: 0000. Replacing other devices requires re-pairing. Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not show the actual color of the item. Thanks for your understanding. Included : 1 X Bluetooth 5.0 Audio Transmitter Receiver Adapter 1 X 3.5mm Double Head Audio Cable 1 X Chinese and English Manual