Sound and silence in perfect harmony! InMotion earphones with Etymotic Research technology deliver a perfect combination of near-perfect sound reproduction and dead-quiet noise isolation. While musicians, audiophiles and acoustic engineers have utilized this (ER) technology since the mid 80s, it is now available to enthusiasts anywhere with the introduction of the new inMotion earphones. Engineered to provide a genuinely accurate music stream, these micro earphones assure smooth treble, clear and natural piano, crisp percussion and rich orchestral music. The earphones are shaped to comfort-fit like earplugs, capturing awesome bass within the ear. Importantly, this earplug design blocks out external sound, allowing lower level listening volume and preventing hearing damage and overload distortion from otherwise excessive noise. Perfect silence for beautiful music. Just listen.