INSMA Amplifier Board TDA7492P Audio Receiver Amplifiers DIY Module 25W Dual Channel Fits the 25 W board best fits 8 Ohm and 15W-25W loudspeaker Output Impedance: 4/6/8 Ohm, impedance can drive speakers Chip: TDA7492P, powerful and high efficiency Power supply: 2.1 interface 8-20V steady DC power supply, best with 12V/3A. Overload may burn the board. If you want to connect to higher voltage, please control electricity properly DIP switches can be adjusted directly after the amp gain more respect and better promote greater damping horn