Float keeps trough filled automatically. Trough is deep enough for ducks/geese to get head into the fount. Works with pressurized water system. Float valve is protected by cover. This works great for ducks and geese! Also now comes with all the connectors to hook into a garden hose right out of the box. No need to go to the hardware store and get any fittings! Trough length 29 1/2", drink height 5". 2 gal. capacity.