Zoeller 137-0036 Model 137 Sump Pump 0.5 HP 230 3PH 10' Cord NonautomaticZoeller Model 137 Sump Pump Description Our Model N137 Sump Pump is an all cast iron pump designed to remove unwanted groundwater in basement sump applications. The professional grade, 1 2 HP N137 is great option when a high flow cast iron sump pump is required. The Model 137s switch case, motor housing, pump housing, and base are each constructed of cast iron. Additionally, the Model 137 is designed with a cast iron vortex impeller allowing solids to