DROK&reg; TDA8920 140W(peak 180W) Hige Power Class D Subwoofer Amp Board Speaker Home Amplifier DIY Kit This digital amplifier board uses TDA8920BTH chip, has high efficiency(can exceed 90%). Maximum Output Power: 140W8ohm +/- 25V); Peak Power = 160W; Operating Voltage: DC Dual +/-20V to +/-25V. Two potentiometers, the left is frequency adjustment potentiometer and the right is subwoofer volume control potentiometer. The radiator is after oxidation treatment to ensure best performance, which makes working more stable. Has many advantages, compact design, large power, low noise and long performance life, etc.