Stable Bluetooth Transmission: The advanced Bluetooth 5.3 technology can provide a stable connection for streaming music and handsfree calls through FM frequency. Built-in microphone, supports smart voice navigation from your phone, and it is easy to answer or end a call with one button. No need to hold the smartphone, making your driving safer. Fast Charging: The car charger can fast charge two devices simultaneously through the Type C port (30W Max) and USB port 5V/2.4A (12W Max). Built-in overcurrent protection, overvoltage protection, overcharge protection, overload protection, and short circuit protection, ensure safe charging of the charger. Bluetooth Handsfree Calling: Answer/ reject/ hang up/ recall all in one button. And it can automatically switch between incoming calls and music. Display and detect the vehicle voltage after plugged in. Enjoy voice control and safer driving with this Bluetooth FM transmitter. Hi-Fi Sound Quality & Noise Cancellation: Noise cancellation