heating element,ceramic heater element element,quartz heating tube factory price certification :UL,TUV sell to ... -standard size product. 2)The structure of tubular electric heating element is in a metal tube into the heating wire, and ... : magnesium oxide Tube Material: Stainless steel seamless pipe, welded pipe, copper, yellow brass pipe, carbon steel pipe Common diameter:Φ22,Φ20 ...