Car Bluetooth FM Transmitter: Bluetooth car adapter provides multi-solutions for your hands-free driving and in-car stereo streaming. It features a big display screen offering a wider visual interface for more information, such as incoming phone number, track name, FM frequency, battery voltage, Bluetooth connected device and more.Stronger Microphone for Better Hands-free Calls: utilizes stronger microphone, greatly amplify sound reception and strengthen sound quality, bringing a higher level of experience.Treble & Bass Music Streaming: You can stream music directly from your car radio via Bluetooth, microSD card, Aux out, and enjoy free switching between treble and bass mode, the color spectrum auto-syncs with your music.QC3.0 Fast Charging: It Comes with a QC3.0 charging port to deliver high-speed charging to driver and passenger, the charging time is 4 times faster than conventional charging.Kindly Note: Compatible car cigarette lighter socket dimensions: Diameter (without spring clip): 20mm，Diameter (with spring clip): 24mm, the deepth of the car cigarette lighter socket is 65-70mm. Surface dimensions of the KM30 Bluetooth FM Transmitter: the width of the screen plain surface is 41mm, the length is 85mm, and the thickness is 14-16mm (With rotary button is 24mm). Please compare the size between the transmitter and your car cigarette lighter bofore getting it.