Bluetooth 5.4 & U-Disk: This car bluetooth transmitter uses an upgraded Bluetooth 5.4 chip, which makes the transmission faster, more stable and safer. Provide Bluetooth and U disk as two playback methods.Bass Boosted & Hi-Fi Stereo: bluetooth adapter car just click b to turn on the BASS sound effect with one click. At the same time, it also uses high-quality HiFi technology to restore the real sound and powerful bass, providing the ultimate listening experienceFast Charge: This fm transmitter car bluetooth 5.4 is equipped with 30W PD3.0 and 18W QC3.0 fast charge ports, which can fast charge two devices at the same time and compatible with most smartphone and other fast loading protocolsLED Light Bar & LED Indicator: This bluetooth transmitter uses colorful LED light bar, which makes it easier to find the transmitter faster when driving at night . At the same time, it is equipped with an LED indicator that automatically detects the voltage when startingSafer & Widely Used: Bluetooth 5.4 fm transmitter is equipped with multiple protections such as over-current, over-voltage, over-heat and short-circuit, ensuring safe charging while driving! The frequency range is between 87.5MHz-108MHz. After booting, it will automatically connect to the saved Bluetooth device. Compatible with 12V-24V cigarette lighter sockets and 99% of all smartphones