BP-420-5 Polypropylene Bag Filter - Compatible with a Broad Range of Corrosive Fluids Including Organic Solvents, Oils, Acid, Alkalis and Micro-Organisms The bags are manufactured from felt because of its high solids loading capabilities in comparison to similar mesh fabrics. A glazed finish created by melting the outermost surface fibers is used to produce a bond that reduces the possibility of migration. BP Series (Polypropylene Felt) Bags. BP Series Replacement Filter Bags SP BP 420 5 #4 Polypropylene Felt Bag Filter $3.34 5 Micron Polypropylene Felt Filter A high quality 5 micron glazed polypropylene felt bag filter (20 (18 x 4)) by SpiroPure. Compatible with Pentek BP-420-5 / 155386-03 PP filter... Compatible with a wide range of acidic and alkaline fluids, and other corrosives , Withstands high temperatures Pentek #420 Polypro Felt Bag 5 Micron 155386-03., Polypropylene Felt Filter Bag Pentek #420 Polypro Felt Bag 5 Micron Polypropylene bags are compatible with a broad range of corrosive fluids including organic solvents oils acidsalkalis and micro-organisms. Ametek, Pentek, US Filter Water Filters | Filters Fast Manufactured with felt media for high dirt-holding capacity