Featuring Dynamic MicroDriver, the SE215 delivers detailed sound with enhanced bass. A detachable cable with formable wire enables easy replacement and a secure, comfortable fit on-stage or on-the-go. Sound Isolating sleeves in multiple sizes provide up to 37 dB of isolation and a customized fit. Available in translucent black or clear color choice. Comfortable sound isolating sleeves block up to 37 dB of ambient noise. Sound isolation technology prevents outside noise from interfering with your listening experience, whether on-stage or on-the-go. Shure Sound Isolating Earphones require a proper fit to achieve the best sound.The role of the included sound isolating sleeves is twofold: blocking ambient noise and ensuring a comfortable customized fit. Because every ear is different, the Fit Kit includes three sizes (S, M, L) of the flex and black foam sleeves. Experiment with the size and style that creates the best fit for you. A good seal is key to optimizing sound isolation and bass response as well as maximizing comfort during extended wear.