brand new and high quality. Feature: The appearance of the product is exquisite Using CSR high-end chip design One-key switch between RX and TX modes RCA, I2S -audio input/output interface, can be switched freely Two antennas, Bluetooth-compatible operating distance>80M, strong stability High fidelity and lossless sound quality, ultra-low delay sound output. Support apt-X LL, apt-X, SBC, AAC, FS. Built-in 500MA battery, long battery life There will be a low battery reminder when the battery is below 20%. The product will automatically enter the sleep power saving mode after 6 minutes in the RX, TX mode without connection, and it has its own battery for protection IC, which is safe and reliable while charging Support Dual stream (TX mode) transmission can connect two Bluetooth-audio devices Automatic connection can be realized in receiving mode and transmitting mode, and has memory function for connected products The appearance of the product is exquisite; Specifications: Material: Plastics Size: 11x9x2.5cm Color: Black Bluetooth-compatible Version: BT 5.0 Bluetooth-compatible chip: CSR Transmission distance: 80M (open place) Battery standard: 500MA Quantity: 1 Pc Note: Please allow 0-1mm error due to manual measurement, pls make sure you do not mind before you bid. Due to the difference between monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 1x Bluetooth-compatible 5.0 Tranmistter receiver 1x 3.5mm Aux Audio-Cable 1x RCA audio-cable 1x USB Cable 1x User Manual