With A Wide Applied Range And Practicability, It Can Fit The Majority Of Active Speakers And Power Amplifiers In The Market. The Replaceable 6K4 Vacuum Tubes Design Can Optimize The Circuit. The Audio Part And The Power Part Are Completely Separated, Which Minimizes The Interference To The Sound. The Timbre Is Soft And Beautiful, Sweet And Warm, And With Powerful Bass, Penetrating Treble. With Treble And Bass Adjustment, Single Power Supply, It'S Small And Portable, Brings You Much Fun And Convenience. Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. voltage: AC220V Colour:black Material:Metal Package Contents: 1 * HiFi Tube Audio Amplifier 1 * Power Adapter 1 * English instruction manual Only 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.