The Grainger 14K740 is a 14 gauge, type 1 solid copper electrical wire with THHN insulation. It is rated up to 90°C and 600 volts. This wire comes in multiple lengths, with the most common being 250 ft reels. The copper wire has high conductivity and is designed for use as branch circuit wiring in residential, commercial and industrial applications including wiring of lighting and receptacle circuits. This UL listed wire can be used for both exposed and concealed work.