Spa and Hot Tub Heater, Min. Flow Rate 5/15 gpm, Inlet Size/Bushing Size 1-1/2 in NPT, Unit-Mounted Thermostat Included, Voltage 120/240V AC, 1 Phase, Wattage Output 1.5kW/6.0kW, Amperage 12.5A/25A, Control Type Mechanical Selector Dial, Overall Length...