XP Defender Ear Plugs offers you one of the most innovative ear plug solutions yet. Simply insert these little ear plugs in your ears then decide which mode you want to be in: First, leave the valve open- you’ll hear sound clearly and naturally- almost seems as if your ears aren’t even plugged. Then when loud sounds hit your ears, the Dynamic Mesh Filtering System™ will automatically screen those sounds out protecting your hearing. Second, simply close the valve for total hearing protection. These are small, handy and can go anywhere with you, so you always have hearing protection when you need it without blocking off all your hearing.