Product parameters:Product name: Two-channel Bluetooth-compatible power amplifier boardProduct number:Input voltage: DC 12-24VOutput power: 100x2Audio input: Bluetooth-compatible: TF card, AUXNumber of channels: two channelsNote:After power on, there will be a tone waiting for the Bluetooth-compatible connection, and the power indicator will flash quickly; when the Bluetooth-compatible is connected, the tone will tell you that the Bluetooth-compatible connection is successful, the power indicator will stop flashing, and the indicator will flash at low frequency when playing songs. Three audio input methodsSupport Bluetooth-compatible, TF card, AUX audio input; this amplifier does not support three ways to input at the same time, the system will automatically select the last audio input method. (For example, when you are playing a song in a TF card, you are inserting AUX, the system defaults that you have to modify the input mode and select AUX input.)When AUX input: the power light is always on in red, and the blue light in Bluetooth-compatible is flashing.When the TF card is input: the power light is always on in red, and the blue light is flashing.When Bluetooth-compatible is input: the power light is always on in red, the Bluetooth-compatible light is always on when the Bluetooth-compatible connection is successful, and it flashes when playing songs.