RUBBERMAID STOCK TANK 100 GALLON BLACK RUBBERMAID STRUCTURAL FOAM STOCK TANKS BUILT TOUGH FOR SUPERIOR PERFORMANCE AND LONG-LASTING DURABILITY IN ALL KINDS OF WEATHER EXTREMES. SEAMLESS CONSTRUCTION FOR OUTSTANDING DURABILITY. OVERSIZE DRAIN PLUG MAKES FOR EASY DRAINAGE AND CLEANING OF STOCK TANK. 1-1/2″ OVERSIZE DRAIN. STOCK TANKS ARE GREAT WATERING TROUGHS HELPING TO PROVIDE A BETTER LIFE FOR LIVESTOCK. OPTIONAL ALL-PLASTIC ANTI-SIPHON FLAT VALVE PROVIDES CONSTANT WATER LEVEL.