Feature: Optional full 206 channels from 87.5 to 108.0 MHz Sleek, rugged design with LED frequency indicator digital screen Detects and displays car battery voltage at startup Support U disk/TF card player/AUX output Support mp3, WMA format music You can use features such as answering, hanging up, rejecting and redialing calls. Stereo music playback Calls with Echo Cancellation and Noise Support (CVC) 12-24V compatible Charging output: 5V/A Automatic power-off memory function Support multiple languages: Chinese, English Specification: Rated working voltage: 12 USB output: 5V/1A Working temperature: 0-50 Supported playback formats: MP3 WMA Signal-to-noise ratio: >60dB Distortion: <0.1% Frequency Response: 20Hz-15Khz Left and right channel separation: >60dB BT version: Version 4.0 + EDR Sound Processing: A2DP (Advanced Audio Distribution Profile) Transmission distance: 10M Microphone effective range: 0.5-2M FM transmission frequency: 87.5-108Mhz FM transmission mode: Stereo digital phase-locked loop phase-locked The package includes: 1pc*mp3 player 1 pc * User Manual Operation Manual: Plug the FM transmitter into your car's cigarette socket to get power and search for this device. Find an empty station and keep the FM transmitter and car FM radio on the same frequency.