About this item Easy to use -- You should adjust FM transmitters and car radios, make them at the same frequency. Then let your phone or audio player connect this FM transmitter via Bluetooth/audio line. Dual USB Car Charger - fast charging technology with 5V/2.1A charging ports, one designed for charging and other to read USB files Larger display display - 1.4 inch large display can display incoming call number, voltage level in car battery, volume, FM frequency and song name if you play music from Micro SD card or USB flash disc. Easy to read at night and day. Great Sound Quality -- More stable FM signal, better anti-interference performance, enhanced audio experience and built-in microphone with Echo Shut-off and Noise Canceling (CVC) technology, offers hands-free calls and wonderful music. Flexible and comfortable - the flexible neck can be adjusted to the perfect viewing angle for comfortable use; the memory function allows automatic connection to the latest paired phone possible.