Screw Plug Immersion Heater, 1, 500 W Watts, Sheath Material Copper, Screw Plug Material Brass, Watt Density 73.63 W/sq in, Heater Voltage 120V AC, 1 Phase, Overall Length 10 7/8 in, 1 1/4 in NPT, Enclosure Type NEMA 1, Min. Immersion Depth 7 1/4 in, Special Information Corrosion-Resistant Electrical Wiring Hardware, Recompacted Element Bends Restore Insulation Resistance After Forming, Silicone Resin Element Seal Standard, For Use With Clean Water, Non-Corrosive Material, Includes Screw Plug