6J1 Valve Audio Headphone Amplifier Pre-amp Tube PreAmplifier Kit Assembled BoardSpecification:Color: BlackVoltage: AC12V 500mASize: 170×60x28mmFunction: Significantly reduce the "digital taste" and "transistor sound"Feature:Excellent sound effects、 cute and unique appearanceEasy to install、 This column includes two 6J1 tubes、 simply connect the transformer can workDo not have to worry about looking for high-voltage power boost comes with this board allows you to enjoy high-pressure tube at a low supply of charmPacking included:1 x Headphone amplifier