No output filter required; single-ended inputExcellent " on, down" noise suppressionNo impact sound when switching on and offOvercurrent protection, overheating protection, undervoltage protectionThe standard supply is 12V, the current is 3A, and the maximum voltage is 18V ( supply below 12V is not supported). It is recommended to use a 12V3A switching supply for testing.Voltage and settings:Working voltage range: 12V-18VOutput :15W (CLASS D, 12V/4 ohm, THD=10%)20W (CLASS D, 15V/4 ohm, THD=10%)Up to 92% efficiency (18V/8 ohm)colour: green + blackMaterial: plasticPackage Contents:1 x Amplifier BoardOnly 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.