1、Passive Preamplifier Active Speaker Volume Controller: precise volume adjustment, no loss, compatible with all types of playback devices and external active speakers. 2、Professional 128mm Fader Switch for Volume Adjustment: the accuracy error of fader switch is small, the left and right channels are synchronized better, and there is no loss of sound details. 3、Compact \u0026 Exquisite Size: the volume adjuster with intuitive scale designed makes the desktop volume adjustment more convenient and precise. 4、Plug and Play, Simple Installation: able to be used once inserted, convenient to install, signal source non consumption adjustment, no loss of input and output, perfect for you to enjoy different hearing experience. 5、Suitable for Equipment with Excessive Sound Gain: such as computer sound card, DAC decoder, CD player, digital player, active speaker, rear power amplifier and other equipment. Features: Passive Preamplifier Active Speaker Volume Controller: precise volume adjustment, no loss, compatible with all types of playback devices and external active speakers. Professional 128mm Fader Switch for Volume Adjustment: the accuracy error of fader switch is small, the left and right channels are synchronized better, and there is no loss of sound details. Compact & Exquisite Size: the volume adjuster with intuitive scale designed makes the desktop volume adjustment more convenient and precise. Plug and Play, Simple Installation: able to be used once inserted, convenient to install, signal source non consumption adjustment, no loss of input and output, perfect for you to enjoy different hearing experience. Suitable for Equipment with Excessive Sound Gain: such as computer sound card, DAC decoder, CD player, digital player, active speaker, rear power amplifier and other equipment. Specifications: Material: Metal Interface: Gold plating RCA interface Power Supply: No need additionally connect power supply, able to be used once inserted Input and Output Impedance: 10~50KΩ Frequency Responding: 20~20kHz Distortion: <0.002% Output Consumption: <0.01dB Signal Gain: 0dB Signal-noise Ratio S/N: >98dB Input and Output Interface: Standard RCA interface Volume Control Switch: Adopt professional 128mm fader volume switch Item Size: 170 * 69 * 50mm / 6.69 * 2.72 * 1.97in Item Weight: 540g / 19.05oz Package Weight: 660g / 23.28oz Package Size: 21.5 * 15.5 * 6.7cm / 8.46 * 6.10 * 2.64in Packing List: 1 * Volume Controller 1 * Volume Controller