This Anti-Siphon Float Valve from Little Giant will automatically control the water level for most plastic and metal stock tanks, troughs, barrels, and pans. It has an all-metal valve that flows up to 245 gallons per hour and operates at pressures between 20 and 50 PSI, and it has an anti-siphon feature that complies with basic back-siphoning regulations. This model measures 7.5"L x 3"W x 4.2"H and accepts a standard 3/4" garden hose. | Little Giant Trough-O-Matic Anti-Siphon Float Valve with Aluminum Housing