The Wayne 1/2 HP cast iron submersible sump pump is designed for work in sump pits 11 inches or larger. Its ceramic mechanical seal keeps this pump going in even the most demanding environments, and the 1 1/2-inch discharges creates maximum flow and ensures easy installation. It works 9 inches on level or 4 inches off level. A two-pole switch prevents basement flooding in the event that one pole sticks, and disconnecting 115-volt conductors prevent damage from lightning. The automatic overload mechanism prevents damage to motor windings, permanently lubricated ball bearings need no oiling, and the waterproof three-prong grounding wire with an 8-foot extension reaches distant outlets. Wayne backs its pump with a three-year limited warranty.