Whether you are a musician using a personal monitoring system, or a music enthusiast listening to your favorite bands via an MP3 player, the comfort and clarity of the EU-4 will allow you to listen for an extended length of time without fatigue. Extremely light weight, the EU-4 is hardly noticeable once in place. The rubber sleaves are soft and pliable, conforming to the individual's ear cannal for comfort and isolation beyond compare.