Introduction: According to customers's requirements, copper or aluminum conductor is evenly warpped with one or two layers of non-alkali fiberglass. Then it is impregnated i compatible insulated coatings of required thermal class,baked to make a whole between fiberglass and conductor. There are three thermal classes of 130,155,180, four insulation thickness classes of 20,30, 40, 50. Fbiberglass covered alulminum wire is widely applied in transformers, electromagnets, welding machines or similar electrical instrument. The electrical bare copper or aluminum wire with extrusion process is the ideal material for polyimide film wrapped copper or aluminum wire.