The Water heater elements are made of durable copper material with Chrome coating. it's high temperature resistance, corrosion resistance, good thermal conductivity and anti-mineral accumulation. All of them were strictly tested per our pre-shipment quality control process to ensure stable performance and longer service life. 2xPack ?CONTENTS? - Screw-in HWD Universal Water Heater Element - Pack of 2, this thread watt density style heating element can be used in most replacement situations of the same power and voltage. Reduces lime scale build-up when used in areas with hard water. ?Power Material? 4500W @ 240V, High Watt Density at 240V (W/sq. in. ): 208, Cold Resistance (ohm): 12.80, Outer sheath material: Copper Dimensions: Element Diameter 2.5cm, Element Length: Flange to Tip (in. ): 13-9/16", Mounting type: Threaded, Socket size: 1-1/2" ?Compatibility? The Water Heater Element fits most models from American, AO Smith, Bradford White, Craftmaster (before 1991), GE, GS Wood (certain models), Kenmore, Lochinvar, Maytag, Mor-Flo, Reliance, Rheem, Richmond, Rudd, Sears, State, Whirlpool and hot water heaters manufactured after 1994. ?ONE YEAR WARRANTY?UL Listed Water Heater Replacement Part with One-Year Warranty:The hot water heater element is UL listed for USA and Canada.