PSUSA WiseWire 18g Pet Fence Wire 1000ft WiseWire 18 AWG PE30 is a heavy duty high strength flexible copper clad steel wire A custom grade steel core metallurgically bonded with a copper cladding that is uniform and continuous creating a bi metal conductor that acts as one and is corrosion resistant Special annealing and drawing processes are performed during the cladding process to achieve desired engineered benefits of strength flexibility reliability and durability Insulation is a 30 mil high density high molecular weight polyethylene HMWPE HDPE WiseWire insulation is engineered to provide superior water blocking and abrasion properties against underground elements and helps prevent accidental breaks caused by rocks in shifting soil conditions dig ins and corrosion