Isolation never sounded so good. Isolator earphones are a great choice for today"s active lifestyles. They tune out the world around you, so you can hear every detail in your music. These low-profile, in-ear earphones fit comfortably with hats and helmets. Ideal for commuting, travel and sports activities. Best Sound Accuracy--True high fidelity requires reproduced sound to be as close as possible to the sound of a live performance. Etymotic"s earphones have the highest response accuracy of all in-ear earphones. Best Noise Isolation--Etymotic"s ear phones have the highest noise isolation of all earphones. Reduction of outside noise lowers the risk of listening at unsafe levels. Best Style and Fit--All Etymotic earphones include an assortment of noise-isolating ACCU-Fit eartip options to ensure proper seal and comfort.