Transmitter Wireless Bluetooth Receiver 3.5MM RCA Music HIFI Adapter 2 in1 Audio. Wireless USB Bluetooth 5.4 Audio Transmitter Receiver Adapter 3.5mm For TV Car. Hands-Free Calling & NaigationThere is a built-in microphone for hands-free calling, and one MFB button to answer / hang up / reject / redial calls.
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