Attributes . Convertible Design Allows for Use of Both DOE and SOE Filter Cartridges, Epdm Seals, Polished Exterior and Pickle Passivate Interior/Exterior for Enhanced Corrosion Resistance, Stainless Steel Cartridge Support and Sealing Hardware, Threaded FNPT Vent and Drains, Swing Bolted O-Ring Closure Seal Provides Quick and Positive Seal and Easy Access to the Vessel Interior and Filter Cartridges . Names