This product uses advanced double-sided thickened gold-plated PCB (substrate 2MM, copper foil thickness 75U, not comparable to 50U), all music signal channels use military 718 factory resistance (the factory that helps God six generations of resistance), and the resistance is switched through the relay Complete 256-step step adjustment, no popping noise, pure resistance loop, higher fidelity The small size does not take up much space. It can directly replace the high-end potentiometers such as ALPS that integrate successful amplifiers and discrete power amplifiers. The effect is immediately visible The resistance value used in the amplifier is to be notified separately and needs to be customized.Size: 86MM*55MMVoltage: AC dual 12V--18V