The single conductors are stranded copper and each conductor is color-coded for identification purposes. Temperature rating: -40°F to 185°F -40°C to 85°C. YEL,RED,GR,BR - COLOR CODED Trailer cable is manufactured of multiple primary wire conductors covered with a PVC jacket. Trailer cable is ideal for wiring trucks and trailers due to its durability and high resistance to cracking abrasion oil acid and natural elements.East Penn