Parameters: Working voltage DC 9V-18V, recommended DC 12V; maximum output power 2x35W (18V/4Ohm); 4~8 ohm speakers can be connected. Properties: Class AB, 2.0 dual channel. Input: 3.5mm audio line input. Protection: Input reverse connection protection; short circuit protection; overcurrent protection; overheat protection. Features: Volume adjustment knob; immersion gold circuit board; speaker capacitors, channel bulk filter capacitors; black copper terminal blocks; gold plated audio input terminal blocks. Color: As shown Material: PC+Metal Package Contents: 1 x Amplifier Board 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 to differ slightly from the real thing. Measurement allowed error is +/- 1-3cm.