Also called “Sand Shark”, PVC wash-down valves are designed to position well screens in sandy soils and to thin drilling fluids. A ball valve opens under pressure from a water stream and rises into a closed position when the water is turned off. The internal female pipe thread allows the water pipe to bypass the screen for jetting. The outer diameter may be flush thread or slip. Outside diameters are the same as the equivalent nominal pipe size. No Minimum Quantity. Helps shorten development time, improves well yield, used to thin drill mud in bore hole, can be used to jet screen, self-sealing ball. Available with internal threads: 1/2”, 3/4”, 1”, 1-1/4”, & 2” Size 1/2” to 6”.