Model Number: H44-7-#4779 Key Specifications/Special Features: The check valve is closed by the reversing flow medium and the weight and there is a damper on the valve. The check valve is closed by two stages of quick and slow closing which prevents the pump fromTurning back and super high water hammer pressure. The weight on the shaft balance the force during opening to reduce the flow resistanceFeatures:Size: DN80-DN700Materials:Body: ductile iron, cast iron and moreBonnet: ductile iron, cast iron, stainless steel and moreDisc: ductile iron, carbon steel, stainless steel and moreStem: SS416Hinge pin: stainless steelSeat ring: brass, bronze, stainless steelMedium: fresh water, sewage, sea water, air, vapour, acid, alkalis and more