Specification: *Product Name: Bluetooth 5.3 audio adapter transmitter supports APTX *Bluetooth version: Bluetooth 5.3 *Support: protocol A2DP, AVRCP, AFH, HFP, HSP *Working frequency: band 2.402GHz -2.480GHz *Power level: power level 2 (Cla II) *Input interface: USB (free -drive), AUX audio *Power supply method: USB 5V power supply Features: 1.Support dual -stream support Dual STREAM (TX mode) transmitter supports connecting two Bluetooth speakers or headphones (using the same codec) at the same time, dual connection can support APTX adaptive up to 2.Codec AptX adaptive/APTX HD/APTX LL/APTX/SBC. 3.APTX Pay attention to support ADAPTIVE CODEC when connecting a single connection. 4.Input voltage DC 5V. 5.Bluetooth distance (10m) (under the condition of no obstruction and interference). USB Transmitter Function Operation: (For details, see the instructions). Open/shut down and connect the power adapter or computer USB to power on the power supply automatically, and automatically shut down after removing. Tap the button back, double -click to quickly enter the pairing state. Functional Operation: 1.Open the Bluetooth headset and set it into pairing mode. 2.Insert this device to the power adapter or PC host USB, double -click the pairing button, the blue LED light flickered quickly, and the device enters the pairing state. 3.The blue indicator on the device is often on and the connection is succeful. (After connecting a device, the blue indicator is often on. Double -click the button, the green light quickly flashs the second device to connect to the second device. After the succeful second device is connected, the green indicator is often on).