The NIBCO® ductile iron butterfly valve provides ease of operation with quarter-turn (90 degrees) open to close. 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. The unique molded-in EPDM seat liner with stainless steel disc is recommended for chemical applications the liner compatibility will permit. Please refer to NIBCO technical data sheets,more 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