One-way Valve: The emergency face mask is one-way valve that can protect the rescuer during first aid | Good Quality: Our CPR masks are made of high quality nylon pouch and polyethylene fiber | CPR face shield is very compact 1.96" by 1.96" , nylon keychain with ring, easy to carry around | Mutifuntion Tool: It is both an emergency face shields and a key chain kit that can easy to use | Can be put into any first aid kit for its compacted shape. Great for glove compartment, boat, purse, keychain or home