Rheem HP40RH HP-40-Super Efficient 40-Gallon Heat Pump 240-Volt Electric Water Heater High 2.0 Energy Factor (EF) 3 Operation modes: Energy Saver (heat pump); Normal (heat pump with element backup); Electric Heat Only (two elements) 2.5-Inch Non-CFC foam insulation Premium resistored anode rod protection, extends tank life Exclusive Rheemglas tank lining