Abstract: Prosthetic valve means for use in heart surgery includes a retainer ring member designed to be attached to portions of a living heart. Leaflet means are supported for hinging movement in the retainer ring to simulate the movement of heart flaps in a human heart. The retainer ring means has inner peripheral wall portions removed to form spaced apart apertures in which occur hinging sockets for receiving hinging stud portions of the leaflet means. The spaced apart apertures are further characterized by upper and lower stop edges against which the leaflets may seat in an alternating manner and the stud portions are freely supported in respective sockets to provide for floating a leaflet in the paths of travel of a flow of blood during the systolic and diastolic functioning of a human heart.