UNIQUE CENTER ADAPTER DIRECTS EXHALED BREATH AND MOISTURE DOWNWARD, AND HELPS REDUCE DEBRIS FROM DEPOSITING IN THE VALVESMOOTH SURFACE ALLOWS FOR QUICK AND EASY CLEANINGLARGE LENS PROVIDES A WIDE FIELD OF VIEW AND EXCELLENT VISIBILITY3MTM COOL FLOWTM VALVE PROVIDES COOL, DRY COMFORTLIGHTWEIGHT WELL-BALANCED DESIGN AND SILICONE FACE SEAL FOR ENHANCED COMFORT AND DURABILITY