1:4.2 Bluetooth chip, intelligent noise reduction, clearer calls. 2: Lossless audio decoding. High-resolution, high-performance stereo sound, no lag, and supports lossless music playback such as MP3/FLAC/WMA/APE. 3: U disk/TF card playback. Compatible with all brands of music USB flash drives/TF cards on the market, the extended playback mode up to 32GB supports free switching. 4: Memory playback after power off. It automatically reconnects and memorizes the frequency when it is turned on. After the track is powered off and restarted, it will start playing from the first line of the disconnected song. 5: Dual USB smart fast charging. Dual USB interfaces can charge up to 3.1A at the same time, and intelligent shunt technology ensures fast charging without damaging the phone.