MCE Membrane Filter, Sterile, Gridded, Diameter: 47mm Pore: 0.45 Micron, Pack of 100 Mixed Cellulose Ester(MCE) membrane Filter is composed of cellulose acetate and cellulose nitrate, which is higly biologically inert and widely used in Microbiological analysis of water, wastewater, cosmetic, pharmaceuticals and beverages.