Patson marketing services manufactures check valves as per international standards. The company supplies the check valves in swing and lift type construction with bolted cover in 25 to 300 mm size and pn i/ asa 150 and 300/ din pn 16/ 40 pressure class. The end connections are flanged to international standard materials. These check valves are constructed from is 210 grade fg 200 cast iron; astm a 216 grade wcb cast carbon steel; astm a 351 grade cf8/ cf8m/ cf8c cast stainless steel and other standard grades.