Master Plumber, 1/3 HP, Cast Iron, Submersible Sump Pump, 115V, 1 Phase, 1-1/2" Discharge, 2 Pole Switch Design Allows For Operation In Sump Diameters Of 10" Or More, No Switch For Control Panel Or Manual Operation, Rugged, Oil Cooled Motor Provides Continuous Bearing Lubrication & Maximizes Heat Dissipation, Lubricated Ball Bearings & Shaft Seal For Longer Service Life, Shaded Pole Motor Eliminates Failure Prone Switches & Relays, Long Life Carbon/Ceramic Seal Protects Motor Against Water Leakage, Heat Sensor Overload Protection With Automatic Reset When Motor Cools To Safe Operating Temperature, Anti-Airlock Hole In Base Reduces Added Labor Pump, Intake Screen Volute Base, Switch & Power Cord Are Serviceable.