A metal plate for a dual plate check valve includes a substantially circular segment shaped plate member of a predetermined substantially uniform thickness and is pivotally mounted to enable rotation about an axis substantially parallel and adjacent to a chord. The plate member has a central portion and two extreme end portions distal to the central portion. The end portions are provided with reinforcements thereby increasing the thickness of the plate member in the end portions, the reinforcements being located so that when the plate member of the check valve is in a closed position, the end portions with reinforcements are in a radially outward direction from the valve seat of the check valve. When back pressure acts on the plate member, the reinforcements enable the plate member to distort substantially uniformly to maintain sealing contact with the valve seat.