No output filter requiredsingle-ended inputExcellent " on, down" noise suppressionNo impact sound when switching on and offOvercurrent protection, overheating protection, undervoltage protection supply voltage: DC12-18VSupply current: 3AOutput : 2x20W outputImpedance: 4-8 ohmNoise ratio: 98dBVoltage 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)The 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.Colour: greenMaterial: plasticSize: 96 x 48mmPackage Contents:1 x Amplifier BoardNote: Because this board has a tuning function, the maximum is 2x20W when the full volume is turned on, and the volume may be attenuated during tuning Only need to be louder without distortionThere is no manual, please confirm the knowledge of Bluetooth USB circuit board connection before placing an order.Only the above package content, other products are not included.Note: Light 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.