1.material:spunlace non-woven 2.Packing:50pcs/ box, 20 boxes/carton Product DescriptionThey are made by three layers, nonwoven, non-poisonous, non-smelling and non-stimulating materials with high-efficient filtering ability. They have high filtration efficiency 99% and are ideal for hospital, dental, clean room and food preparation and industrial environments. They come in two primary styles, ear ...