With DC isolated power supply: suitable for modifying speakers, amplifiers, and adding Bluetooth functions to cars to solve common ground current sound and noise When TWS is used with boxes: the highest protocol APTX Clear TWS pairing information: the highest protocol LDAC (5125 default), Qualcomm 5.1, AAC/APTX/APTXLL/ATPXHD/LDAC, power on, TWS with boxes, AUX audio input, Support IPEX generation antenna, with mobile phone volume synchronization, support serial port AT commands (115200) Support Android APP to modify Bluetooth name (support any language), pairing password, custom EQ, switch prompt tone KCOM is the common end of the button, and the other end of the button is connected to VOL+, VOL-, N/V+, P/V-, PLAY Button Description: "VOL+": short press to increase volume, long press to increase volume; "VOL-": short press to decrease volume, long press to decrease volume; "N/V +": short press to play the next song, long press to increase the volume; "P/V-": short press to play the previous song, long press to decrease the volume; "PLAY": short press to play/pause Special function description: "PLAY": long press for 3 seconds and release to force entering pairing mode, long press for 6 seconds and release to clear the pairing list "PLAY"+"VOL+": long press for 1 second at the same time to enter the host mode to search TWS (with prompt sound) "PLAY"+"VOL-": long press for 1 second at the same time to enter the slave mode TWS is searched (with prompt sound) =Sound) "VOL+"+"VOL-": Press and hold for 1 second to disconnect TWS "N/V+"+"P/V-": Press and hold for 6 seconds to release, clear TWS pairing information and pairing password, reset (with a prompt sound) MODE/TWS key: Bluetooth is not connected to the mobile phone: Short press, host mode searches TWS (with a prompt sound); Double click, slave mod