NIBCO® ductile iron butterfly valves provide ease of operation with quarter-turn (90 degrees) open to close. The unique FKM fluoroelastomer molded-in seat liner with stainless steel disc is recommended for chemical applications the liner compatibility will permit. With the internal stem/disc geometric drive design there is no need for pins or bolts that may create leak paths or turbulence in the waterway. An extended neck allows for insulation up to 2 inches. Please refer to NIBCO technicalmore data sheets, chemical resistance guides and catalogs for engineering and installation information. Choose NIBCO® butterfly valves for the most specified, versatile and economical valve option in commercial, mechanical and industrial applications. NIBCO® butterfly valves are backed by the NIBCO 5-year 125% limited warranty. less