Bramec's 15002 18-4 UL CL2 Thermostat Wire consists of a tubed PVC jacket over untwisted insulated conductors. The wires are 18 AWG solid bare copper. They are compliant with UL Standard 13; NEC Article 725. Temperature Rating: -20 to 60°C. Operating Voltage: 300 Volts max. Capacitance: 25 pf/ft nom. Characteristic Impedance: 100 Ohms nom. DC Resistance: 6.5 Ohms/M' at 20°C. Flame Rating: UL 1685 Vertical Tray.