1. EDR Class 2 A2SP & AVRCP HSP. Middle button: Accepting calls and starting-stopping.
2. RGB color illuminated on/off button. Right button: Volume up - skip to next song.
3. Wireless connection up to 10 meters.
4. 3.5mm stereo audio input. Left button: Volume down - previous song transition.
5. Connection between wireless speaker and 3.5mm headphone.
Go Des GD-BT39 Wireless Audio Receiver Bluetooth 5.3 Adapter with Aux Input. Bluetooth v5.3. Supports Bluetooth stereo audio connection. Echo canceling and noise suppression technology. Automatic device shutdown memory. Direct access audio input.
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