This Cable Applications: Wiring of thermostat controls, heating & air Conditioning equipment, doorbells, ouch-plate systems, burglar alarms, intercom systems, annunciator and bell systems, remote control units, signal systems and other low-voltage applications. Pure Copper Conductors: Our thermostat cable is built with solid pure copper conductors, providing maximum conductivity and reliability to ensure that your systems run smoothly. CMR (Riser-Rated): Our cable is designed with your safety in mind. It features a CMR/CL3R/FPLR (Riser-Rated) flame-retardant rating that provides peace of mind in case of fire. 300V (CL3) Power-Limited Circuit Cable: Our cable is rated at 300 volts and classified as a Class-3 (CL3) Power-Limited Circuit Cable, capable of carrying a surge of up to 300 watts. Sunlight Resistant and RoHS Compliant: Our cable is designed for both indoor and outdoor use, complying with the UL 1581 sunlight resistance requirement for outdoor installations.