Tie On Masks are made of soft,non-woven polypropylene. The 3-ply pleated design offers 0.05 micron filtration at greater than 99%. A full length flat aluminum wire forms comfortably to the nose and face to maintain an excellent fit for maximum filtration. Masks are fluid resistant and disposable. Tie-On Masks are secured with two pair of polypropylene ties. MASKS ARE LATEX FREE. 50/pk