Great way to split one signal output to two audio devices, be it two headphones for you and a friend while travelling, or two different sound systems at home (yes some people are that extravagant). People should know two more things about these adapters in general: First, when splitting a single audio signal into two, the strength of that audio signal is diminished. You may have to turn up the volume on both audio devices to get a louder signal. Second, the device works in reverse - plug in two audio sources into this adapter, and they can both feed into one audio device. A very versatile and handy adapter for people who may not necessarily have an expensive multiple input/output receiver for their home theater.