This is a wireless Bluetooth audio transceiver that integrates Bluetooth stereo audio transmission and reception. It uses Bluetooth 5.3 protocol and supports the memory of the last automatically connected Bluetooth device and automatic reconnection. The module can be configured to work in Bluetooth audio transmitting mode or Bluetooth audio receiving mode by pressing the button. The transmitting mode and the receiving mode are distinguished by two . This model has no built-in battery and can be powered by a 5V power input through the machine's TYPE-C USB interface. This product is widely used in fields that require Bluetooth audio reception, Bluetooth audio transmission, wireless audio transmission, DIY modification and other fields. When configured in Bluetooth audio transmitting mode: You can communicate with the machine configured in receiving mode via Bluetooth wireless It can also transmit stereo audio signals via wires, and can also be connected to some Bluetooth headsets and Bluetooth speakers to wirelessly transmit audio signals to these Bluetooth receiving devices. Statement on product compatibility: When this product is configured in transmitting mode, it is only guaranteed to be perfectly compatible with our Bluetooth audio receiver, Bluetooth audio receiving module, or this model configured in receiving mode. It is not guaranteed to be compatible with other manufacturers on the market. If you want to connect Bluetooth receivers from other manufacturers and encounter incompatibility (such as: unable to connect, no sound after connection, etc.), we have no way to solve it. Friends who mind, please buy with caution!) When applied to wireless audio transceiver solutions, it is recommended to use two machines together, one set as a transmitter and the other as a receiver, and audio signals are transmittedwirelessly between the two machines. Colour: Black material: metal Package Contents: 1 x adapter 1 x Type-C power cord 1 x 3.5mm audio cable 1 x 3.5mm to RCA cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.