Ultra-compact stereo headphone amplifier for studio and stage applications. With 4 headphone output channels and 1 input channel. The volume of each output channel can be controlled independently. Provide the highest audio quality for each headphone even at maximum volume. Adopt ultra-low noise JRC4580 chip operational amplifier to provide excellent audio performance. Adopt high overload capacity, high precision, large capacity, low loss HIFI audio dedicated capacitors. Equipped with DC 12V power adapter. 100% Brand New Model:HA400 PRO Voltage:DC12V Voice Configuration:JRC4580 Plug Type:US Plug, it applies to Canada, India, Mexico, Thailand, Taiwan, the United States, the Philippines and so on./EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Voltage:AC110V/AC220V Colour:Black Material:Aluminum Alloy Size:about 1.22x2.24x4.09 inches<br><br>Package Contents: 1 * 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.