Hattersley butterfly valves are compact quarter-turn isolation valves with an elastomer-lined (EPDM or nitrile) body for resilient, bubble-tight shutoff, available in wafer or lugged configurations and operable by lever or gearbox. They are primarily used for on/off service (though suitable for light throttling) and are offered in a wide range of sizes and construction options (ductile iron bodies, bronze or stainless discs) for applications up to typical PN16 or higher ratings.