Product: Small Power Amplifier AK-280 Amplifier body, dedicated adapter, English instruction manual Mini Stereo Amplifier 40W x 2: Independent treble and bass adjustment ±10dB, for car/home use, 155mm ultra-small, blue LED The output of 40W + 40W is a catalog value; we have not measured it. The following is automatically entered by Mercari: Hi-Fi Audio Amplifier AK-280, with bass and treble adjustment function, AUX input compatible. - Model Name: AK-280 - Function: Hi-Fi Audio Amplifier - Connection Terminals: AUX input - Volume Adjustment: Volume knob with blue LED - Adjustment Functions: Bass and treble adjustment knobs - Accessories: Instruction manual, AC adapter Thank you for viewing.