1.Top ring material 304/316L/Stainless Steel material 2.Independent development mould ... . Punctual delivery time.5.Best after sales service is provided.File formatsPro/Engineer, Auto CAD(IGS,DXF,DWG,STP,STL and ... various kinds of venturi, Top cage, the bottom, the split ring and related accessories, with steel, aluminum and stainless steel as ...