4-AWG Copper THW building wire in black color, has 60-mil thermoplastic insulation that offers protection against electrical threats. This building wire has voltage rating of 600-Volts and current rating of 95-Amps at 90 deg C. It has outside diameter of 345 mil. This 2500-ft building wire comes in reel. It is suitable for services, feeders and branch wiring applications. Building wire is UL listed and meets Federal specification.