Product parameter description: Rated working voltage: 12V-24V Operating temperature range: 063 Support playback format: MP3/WMA Frequency response: 20HZ-15KHZ Bluetooth transmission distance: 5M-10M FM transmitting frequency: 87.5MHZ108MHZ Read U disk/Micro SD card capacity: up to 32 QC 3.0/fast charging source IC: CX8825 + 6601Q (QC 3.0 fast charging identification IC) Bluetooth connection distance: 5 meters Mike: 38dB FM transmitting frequency band: 87.5108MHz Bluetooth, T card, U disk, playback current: 63ma81ma Power on display battery voltage: error +/-0.3V Current noise: no noise Sound distortion: no distortion Car charger limit voltage: 1130V Operating temperature range: 053 Play pause function: short press the phone button Incoming call to answer the call: click the phone button Unnumbered redial function: double-click the phone button Reject a call: long press the phone button Hang up the call: Click the phone button Bluetooth wait for connection prompt: POWER ON-Bluetooth Prompt for successful Bluetooth connection: Bluetooth Connected Volume function: Rotate the phone key knob to adjust the volume T card/U disk support playback format: MP3 / WMA / FLAC Auto-connect after power-on: automatically connect to the last connected mobile phone when power-on No-load voltage of slow charge charging port: 55.25V Slow charging port charging 1A: 4.75V5.25V Net weight: 49g Product gross weight: 74g Packing size: 11.2*7.2*5.5 CM