A cup-shaped recess has four circularly arrayed ports, hot and cold inlet ports on opposite sides and two outlet ports in quadrature relationship. A valve post projects from and registers with the four ports. The post provides laterally opening hot and cold water openings at its outer end controlled by a cylindrical valve member, and at its outer end a pair of slots. The post has large passages establishing the requisite communication between the four ports, the hot and cold water valve-controlled openings and the slots.