Price history on Walmart.com for
Miller Plas Anti SiphonTrough-O-MaticSee on Walmart
"The Miller Manufacturing Anti-Siphon Float Valve automatically controls the water level for most plastic and metal stock tanks, troughs, barrels and pans. This all-plastic valve flows up to 375 gallons per hour and operates between 20-50 psi. This Trough-o-Matic float valve is made from Brand-Miller manufacturing and complies with basic back-siphoning regulations. The plastic housing is molded from high-grade polystyrene for added strength and durability. This valve measures 7.5"" x 3"" x 4.2"" and accepts a standard 3/4"" garden hose. This is a good way to automate the water supply to tanks, troughs and barrels. It is easy to install."... read more.