This magnet wire meets the NEMA MW-80-C standard for operating temperature (155°C/311°F) and insulation makeup.5 Lbs, 49880' Length, 0.0044" Diameter, Natural The insulation is made from modified Polyurethane with a polymide overcoat, and protects the coiled wire from short-circuiting. Raw copper is drawn to meet specific size requirements based on the National Electrical Manufacturer’s Association (NEMA) standards.