Highlight description: A?A?ABluetooth Transmitter & Receiver 2 in 1A?A?A??It supports both Bluetooth transmitting and receiving, namely TX and RX Mode. Adding Bluetooth function to your old TV, desktop computer, and home sound system like boss wave. Making your old car and wired speaker /headphone Bluetooth function enabled. Detailed description: Material: ABS Size: 65 x 39 x 16 mm Bluetooth version: 5.0 Charging voltage: 5V Charging current: 50mA Working current: 5mA Shutdown current: 41uA Battery capacity: 280mAh Charging time: about 2 hours Working hours: about 8 hours Bluetooth transmission distance: 10 m Bluetooth microphone effective distance: 0.5~2 m Bluetooth sound processing: with DSP technology and A2DP (Advance Audio Distribution Profile) function Bluetooth frequency: 2.402-2.480GHz Bluetooth transmit output power: 6dbm Instructions: No reflection on boot A?Toggle the RX-TX button and press and hold the power button again . Insert the charging cable to charge the Bluetooth player for 5 minutes, then turn it on Can't play A?Make sure that the connected device is working properly A?Clear Bluetooth pairing, re-pair Bluetooth A?Whether the audio cable is inserted in place Can't charge A?Please unplug the charging cable and plug it in again . Try another charger No response when switching on Press and hold the power button for 8 seconds to restore the factory settings, and then power onNotes: Please allow slight deviation due to manual measurement. There may be slight chromatic aberration due to the differe