The utmost earphone upgrade - isolation 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 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 Premium materials for a premium sound - the original memory foam earphone tip; made in the USA (of U.S. and imported goods) using proprietary memory foam materials for the ultimate in ear headphone upgrade