The 3M™ Secure Click™ Inhale & Exhale Valve is a replacement part for 3M™ Secure Click™ HF-800 Series Half Facepiece Reusable Respirators. Easy to install, this piece can help extend the service life of your facepiece. If the valve on your 3M™ Secure Click™ HF-800 Series Half Facepiece Reusable Respirator with Speaking Diaphragm is damaged or worn, reach for this replacement part for continued protection against a variety of gases, vapours, and particulates.The 3M Secure Click Inhale & Exhale Valve can be used on the following models: 3M Secure Click Half Facepiece Reusable Respirator HF-801SD, 3M Secure Click Half Facepiece Reusable Respirator HF-802SD, and 3M Secure Click Half Facepiece Reusable Respirator HF-803SD. Each unit is sold separately.