Abstract: A low-cost, two-piece medical valve with improved reliability which can be made utilizing a broader range of materials then heretofore possible and capable of manufacture with easily maintainable molding tolerances. These improvements result from the incorporation of a straight cylindrical seal between the valve core and body permitting limited axial movement. The valve is molded in such a manner to create a strong interlock between the valve ports and to eliminate heavy sections of plastic adjacent to the sealing area of the valve.