Sidco Replacement Elements  Metal End Cap Filter STYLES Metal end caps are available in a variety of configurations and styles. One style constists of one open end and one closed end with a bolt hole, while another variety is a double open end. CONSTRUCTION Standard construction consists of a perforated or expanded core, made of galvanized carbon steel sheet metal. These cores surround either a pleated textile or paper media. Textile media is supported between two layers of epoxy coated screen, while most paper media is supported by outer expanded metal shells. UNIQUE FEATURES Metal end caps may be used for higher temperature environments along with special potting compounds.