ISOtunes TRILOGY™ Foam Replacement Eartips (5 pair pack) Compatible with ISOtunes Xtra (IT-02) and ISOtunes Wired (IT-04). ISOtunes TRILOGY™ Foam Replacement Eartips offer a trifecta of benefits for optimal hearing protection: 1) Superior comfort - super soft memory foam 2) Superior attenuation - made from the best materials available to reduce outside noise 3) Superior sound - durable core material that will not distort sound/music quality