A simple non-return valve consisting of a ball resting on a cylindrical seat within a liquid passageway
A valve regulated by the position of a free-floating ball that moves in response to fluid or mechanical pressure
A shut-off or pressure regulator with an inter-valve ball of resilient material designed to seat on the inner port to provide a positive seal against flow
used to regulate the flow of water and to shut off skimmers, drains and other lines in order to vacuum or run a spa or water feature