Comparison : Item # Series 51 Wafer Body Centric Disc, Resilient Seat (Large Diameter) Butterfly Valves
Item # Series 53 Flanged Body Centric Disc, Resilient Seat (Large Diameter) Butterfly Valves
Item # Series 55 Flanged Body Double Centric Disc, Resilient Seat (Large Diameter) Butterfly Valves