coupling 1) Material:stainless steel 2) Standard:ISO,DIN,JIS,GB ... /alloy steel reducer,concentric/eccentric reducerSizenormal specification and as per the customer requirementMaterialcarbon steel,stainless steel,alloy steel,cast steelStandardISO,DIN ... ,metallurgy,construction,water conservancyPackageseaworthy packing and as per customer requirement coupling