... Name Seamless Steel Tubes for Boiler, Pressure Vessel & Heat ExchangerAmerican Standard ASTM A53,ASTM A106,ASTM A333,ASTM A334,ASTM A556,ASTM A179,ASTM A192,ASTM A210Grade Gr.A,B ... ,STB A22European Standard EN 10216-1, EN 10216-2Grade P235TR1, P235GH, P265GH etc.Size OD1/8"-6"or 8-168.3mm ...