... heating element/electric heater Quality certification :TUV,UL Stainless steel heating pipeFeatures: 1.The structure of tubular electric ... materials: magnesium oxideTube Material: Stainless steel seamless pipe, welded pipe, copper, yellow brass pipe, carbon steel pipeCommon diameter:Φ22,Φ20,Φ18,Φ16 ... requirements. Quality guarantee, welcome to inquiry. Stainless steel heating pipe used for boiler