The 3M™ Exhalation Valve Filter 604 is designed to help filter the exhaled breath of the respirator wearer and provides source control when worn with the 3M™ Reusable Respirator Half Facepiece 6000 Series. It can be easily installed and removed from 3M 6000 Series Half Facepiece Reusable Respirators, and users can conduct a positive pressure seal check while installed. The hard case can be wiped with disinfecting wipes used for 3M 6000 Series Half Facepiece Reusable Respirators. Users should replace the Exhalation Valve Filter if damaged, if the filter media becomes soiled, or if breathing becomes difficult. NIOSH approved accessory only for use with 3M™ 6000 Series half facepiece respirators with 3M particulate filters 7093, 2091 or 5N11/501/603. Not FDA cleared for use as a medical device for use in surgical applications.