Rated working voltage: 12-24VWorking temperature: -20 to 50 degrees Frequency Responese:20Hz-15Khz Bluetooth Audio Processing -:A2DP (Advance Audio Distribution Profile)Bluetooth transmission distance:15mFM transmitter frequency:87.5--108.0MHZUSB charging output:5V / 1000mADigital Media Format:CD，Mp3Bluetooth speakerphone，built-in microphone，convenient and safe to answer the phone，call the noise processing CVC， wind noise reduction.