The E3c combines precision components and remarkable sound isolation to provide studio quality sound everywhere you go. High energy micro-speakers deliver great tonal balance across the entire frequency range. Flexible sleeves produce remarkable isolation, revealing the subtle details of original recordings. The small compact earphone design fits securely in your ear, making it ideal for active listening and frequent travel. The E3c's ear sleeves can even be custom-fit by a hearing specialist, after your purchase, for the best personalized fit and comfort.