Solid Bare Copper Conductor Wire with Oleoresinous insulation -30°C to +155°C Temperature Rated MIL-W-583, Class 155 Rated 1/4 Pound (1/4#), 785 Foot Spool of 30AWG solid bare copper conductor wire with Oleoresinous insulation. Ratings: Temperature -30°C to +155°C, MIL-W-583, Class 155.