1 All stainless steel material 2 Zero leak 3 Low torque 4 High quality, ... 5 In the water industry is very popular sanitary stainless steel valve,butterfly valve,pneumatic valves. Specification: DN50-600Temperature:-35°C ... of Disc: Stainless steel, Plated Ductile cast iron, Ductile iron coated PlasticMaterials of Seat: EPDM,NBR,PTFE Materials of Stem: Stainless steel, Carbon steel