Pre-installed conductors within an overall protective metallic interlocked armor. 45 percent lighter than steel MC cable. Cable reverse wound for ease of pulling and installation. Conductors - solid bare annealed copper per ASTM B-3, stranded copper stranding per ASTM B-8 for conductor. Conductor insulation rated 90 degree Celsius dry, 75 degrees Celsius wet at 600 volt. Conductor insulation is flame retardant, heat resistant PVC with flame conduit fished or embedded in plaster installed in cable tray and as aerial cable on a messenger. UL classified. 1, 2, and 3 hour through penetration firestop systems: W-L-3110 W-L-3113 W-L-31120 W-L-3121 C-A-J-3115. 20 amp. 12/3 gauge x 250 ft.