No output filter required; single-ended input Excellent "power on, power down" noise suppression No impact sound when switching on and off Overcurrent protection, overheating protection, undervoltage protection The standard power supply is 12V, the current is 3A, and the maximum voltage is 18V (power supply below 12V is not supported). It is recommended to use a 12V3A switching power supply for testing. Voltage and power settings: Working voltage range: 12V-18V Output Power: 15W (CLASS D, 12V/4 ohm, =10%) 20W (CLASS D, 15V/4 ohm, =10%) Up to 92% efficiency (18V/8 ohm) colour: green + black Material: plastic Package Contents: 1 x Amplifier Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.