CD-C, CD, DISC, SRC, CD/AUX, etc. DISC+/DISC-, etc. for the upper and lower discs (1-6) Short press Track +Seek / Track- Seek, etc. for the upper and lower songs (1-99). long press Track +Seek / for single repeat / sequential play switch long press Track -Seek / random play. the volume, pause, mute and host operation are the same,Bluetooth priority, play U disk after disconnecting Bluetooth, no U disk switch to AUX. Use media software to convert AAC, APE, FLAC, OGG, DTS, WAV 5.1 and other formats into WAV playable format Bluetooth phone MIC defaults to running in the background, no matter which option can be used, press the previous song to connect to the phone, press a song to hang up the phone. Product voltage: self-powered (12V) car disc interface without external connection Support decoding format: 1 WAV / MP3 Support external: 1 USB2.0 / AUX Frequency response: 20-20K Hz Bluetooth version 4.2 BR/EDR (compatible with versions below 4.2) Distortion: Less than 0.05% Signal to noise ratio: Greater than 90dB Standby power consumption: Greater than 0.1W Working temperature -20 - +70C Working power: DC11-15V (generally taken from the host, no external power supply required) USB output: DC 5V/300mA car button function (or refer to the car manual) Material:ABS colour:Black Package Contents: 1 x Module Unit 1 x Wire Harness 1 x Mic Cable Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.