Duplex 2205 bolts and nuts consist of 21% Cr, 2.5% Mo.and 4.5% Ni and N alloy. It has good property of  corrosion resistance and impact toughness, better than 316L and 317L. This client is automation research and design institute, a scientific enterprise in industry of chemical equipment , material and corrosion, online analysis instrument and attend in the design of environmental equipments, their mixers have strict quality requirements on fasteners, after many times communication, we finally become supplier of their mixers.