Spa and Hot Tub Heater, Min. Flow Rate 5 gpm, Inlet Size/Bushing Size 1-1/4 in NPT, Unit-Mounted Thermostat Included, Voltage 120V AC, 1 Phase, Wattage Output 1.5kW, Amperage 12.5A, Control Type Mechanical Selector Dial, Overall Length 11 in Immersed, Overall Width 14 -5/8 in, Heating Method Immersion, For Use With N15/03099/N15/03100, Standards UL Recognized