Shower Drain Systems A compact, full capacity shower drain system. Automatically turns on after the water starts, and shuts off when the water is removed. Activated by a Rule-A-Matic® float switch. Three inlet ports which offer varying combinations of inlet hose. Other features include a clear screw down cover, a removable strainer for easy cleaning, and an internal check valve to prevent back flow. Flow Rate: 800 gph Discharge: 3/4 inch Inlet Ports: 3/4-1 1/2 inches