Ultra-compact stereo headphone amplifier for studio and stage applications. Features 4 headphone output channels and 1 input channel, with independent volume control for each output channel. Delivers high audio quality to each headphone, even at maximum volume. Equipped with ultra-low noise JRC4580 operational amplifier for excellent audio performance. Uses high overload capacity, high precision, large capacity, low loss HIFI audio dedicated capacitors. Includes DC 12V power adapter. Model: HA400 PRO Voltage: DC 12V Audio Configuration: JRC4580 Plug Type: EU Plug Input Voltage: AC 220V Color: Black Material: Aluminum Alloy Size: approximately 1.22 x 2.24 x 4.09 inches Package Contents: 1 x Audio Amplifier 1 x Power Adapter 1 x English Instruction Manual Note: The package includes only the items listed above. Note: Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement error allowed is +/- 1-3 cm.