The utmost earphone upgrade - isolation plus replacement ear tips are engineered to create a custom in-ear fit to block out external noise and provide a good audio experience with enhanced bass Integrated wax guard keeps earwax and debris out of the earphone’s nozzle to protect your earphones and keeping the sound path open Compatibility - 400-series fits Beats by Dre, Skullcandy, Audio-technica and more; multiple core sizes allow you to find the ideal fit for your earphones; find your compatibility at manufacturer's website Enhanced comfort - soft memory foam reduces earphone irritation and fatigue while reducing outside noise; comply foam is 30x softer than silicone tip material so you have the most comfortable earphones Enhanced sound and fit - body-heat activated memory foam adapts to ear canal to provide a ideal seal and snug fit to keep your while blocking external sound