... valves provides easy breath replaceable catridge Half mask air purify respirator*Soft PVC durable facepiece ensure a tight fit, available color ... provide easy breath.*Replaceable cartridge: available in dust filter, and chemical filter, color of cartridge cover: black, yellow, white.*Cotton ... , and packing is 10 pcs inside a box.FTR3004: Chemical cartridge, and packing is 10 pcs inside a box.Please ...