Bluetooth 4.0 Stereo Audio Receiver Module Wireless Speaker AmplifierDescription (about the interface):Power supply:  - VCC: access the positive pole (3~5V)  - GND: access the negative poleSerial ports:  - VCC  - GND  - TXD  - RXD Funtion: for data transmission、 voice play and status queryAudio:  - AUX: audio input interface  - MIC: microphone input interface  - AUDIO: audio output interfaceButtons:  - VOL+: volume up  - VOL-: volume down  - NEXT: next song  - PREV: previous song  - P\/CALL: play \/ pause (short press)                    answer \/ hang up the phone (short press)                    call back (long press)                    re-pairing (long long press)Note:The microphone is not included.Package included:1 !#!amp!*!times; Module