Southwire 500 ft. 18/3 Solid Copper Thermostat Wire (Pack of 500)The Southwire 500 feet Brown 18 3 Thermostat and Bell Cable is designed for use in heating and air conditioning controls as well as in alarm systems. This cable offers a flat design. The insulation is made of 6 mils of polypropylene and a brown PVC jacket. UPC: 032886438523 Manufacturer Part No: 64168845 Wire Length: 500 ft. Brand Name: Southwire Cable or Wire Type: Copper Stranded or Solid: Solid Gauge Conductors: 18 3 Product Type: Thermostat Wire