1Stereo 2 In 2 Out: 2 simultaneous sound inputs and outputs can be connected. Separate volume adjustment knobs for listening to music and mixing multiple sound sources (including sound) through headphone and speaker outputs. 6db amplification gain, the first stage op amp is the for NJM4580, the second stage driver is the for NJM4556A high current operation. 2Compatible Devices: Input compatible with DVD, CD, set top box, MP3, TV, cell phones, computers, tablets, turntables, sound cards, guitars, basses, electronic musical instruments, game consoles and more. Output compatible with speakers, subwoofer, reverb, AV receiver, post amplifier, headsets, etc. 33.5mm Interface: Input and output 3.5mm stereo socket, input either channel, both are output, input two at the same time, then the output of the mixed sound, two inputs can be input at the same time two different sources, plugged in at the same time will not affect each other, the output can be connected to two headsets at the same time or two amplifiers sound. 4Rugged And Durable: Rugged metal construction stereo mixer with tight connections and stable operating knobs. Premium components and extremely rugged construction ensure a long service life. Compact and lightweight, easy to carry. Please use a premium low ripple power supply. 5Applications: Small stereo mixer, ideal for stage and studio performances or applications requiring multiple headphone connections. Easy to use if you have two or more sound setups on your computer or are listening with a stereo amplifier. Works great for listening to music or watching TV.