1. 4 Headphone amplifier with 5pcs adapters, Headphone amplifiers are specifically designed for headphoneand are used primarily to push high-power, high-impedance headphones. 2. 4 high-power amplifier, Each output channel with volume control for setting volume independently, Highest quality even at maximum volume levels. 3. SupportS 10-150 ohm Headphone, 6.35mm AUX Input and Output, 100Db and +N 0.0003%, Possibility to Output not just Louder Sound, but a and More Real Stereo Sound without Distortion.(Includes 5pcs 6.35mm (1/4 inch) to 3.5mm (1/8 inch) adapters) 4. Aluminum Matte , High-quality components and exceptionally rugged construction . 5. Universal Compacity, Ultra-small headphone amplifier system for studio and stage applications. Plug Type :EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Voltage: 12V(Out); 110-240V(In) Input Jack: 1/4 inch TRS Connector, Stereo Output Jack: 1/4 inch TRS Connector, Stereo Colour:black Material:Metal Size:10.4 x 5.7 x 5cm Package Contents: 1 x 4 Channel Headphone Amplifier 1 Adapter 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.