Analog differential output (RP, RN, LP, LN) When TWS is used with a box: the highest protocol APTX Clear TWS pairing information: the highest protocol LDAC (5125 default). Support serial port AT commands, 115200, N, 8, 1 Support Android APP to modify Bluetooth name (support any language), pairing password, custom EQ, switch prompt tone. 5125 supports SBC, AAC, APTX, APTXLL, APTXHD, LDAC,Function keys: KCOM, PLAY, VOL+, VOL-, P/V-, N/V+, MODE, high level 3V3 is valid. Bluetooth connection status output foot BT_HL (Bluetooth connected: output high 3V3, Bluetooth disconnected: output 0V). 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 next song, long press to increase volume, "P/V-": short press to play previous song, long press to decrease volume, "PLAY": short press to play/pause/answer/hang up, long press to reject "PLAY": long press for 3 seconds and release to force pairing mode,long press for 6 seconds and release to clear pairing list "PLAY" + "VOL+": long press for 1 second at the same time to enter host mode and search TWS "PLAY" + "VOL-": Press and hold for 1 second to enter slave mode and TWS is searched "VOL+" + "VOL-": Press and hold for 1 second to disconnect TWS "N/V+" + "P/V-": Press and hold for 6 seconds and release at the same time to clear TWS pairing information and pairing password, and reset MODE/TWS key: Bluetooth is not connected to the mobile phone: Short press, host mode search TWS (with prompt sound) Double click, slave mode TWS is searched(with prompt sound) Press and hold for 6 seconds and release,clear TWS pairing information,clear pairing password,and reset(with prompt sound). After Bluetooth is connected to the mobile