Check valve available as below:
CHECK VALVE, 3"x3" 1502FM STD 15K STANDARD CVA-3CFM-S01 138 kg
CHECK VALVE, 3"x3" 1502FM STD 15K REVERSE CVA-3CFM-S02 137 kg
CHECK VALVE 4" X 4" 1002 STD 10K REVERSE 41002-REVWBA 208 kg
CHECK VALVE 4" X 4" 1002 STD 10K STANDARD 41002-STDWBA 208 kg
CHECK VALVE 4" X 4" 1502 STD 15K REVERSE 41502-REVWBA 323 kg
CHECK VALVE 4" X 4" 1502 STD 15K STANDARD 41502-STDWBA 323 kg