DuraWire wires are proudly made in the USA with the finest quality raw materials ensuring a wire that will serve you for many years. These wires are used to create, upgrade or expand your in-ground pet fence containment system. Unlike our competitors that offer wires for inground pet fence that have very thin vinyl insulation, all our wires at DuraWire come with superior grade wire with much thicker High Molecular Weight Polyethylene insulation. There are several reasons to invest in DuraWire wires: • Other companies that sell expansion wires are using copper plated aluminum or stainless steel to cut down on cost. This makes it less durable than the solid copper core that we offer. By using a wire made entirely out of copper gives our wires greater tensile-strength, thermal-conductivity and thermal-expansion properties that offer lower resistance, better signal transmission, as well as better corrosion resistance. Also, our thicker wires have lower resistance and better signal transmission over a long range. • Instead of very thin insulation used by our competitors, we use superior insulation made from a polymer known as High Molecular Weight Polyethylene (HMWPE). HMWPE insulation is designed to provide excellent oxidative stability, toughness, and abrasion resistance. It is thicker than vinyl insulation and protects the inside wire from freezing conditions, sunlight exposure, contraction and expansion of the ground, water exposure and general wear and tear. DuraWire wire is compatible with PetSafe, SportDOG, Innotek, Invisible Fence, Dog Watch PetStop, Contain Your Pet, Dog Guard, Perimeter, Dogtek, Dogtra, Guardian, Havahart and all other brands of in-ground electric dog fence systems. For proper system performance, the splice connection must be waterproof. We recommend using PetsTEK Waterproof Wire Splice Kit which include gel-filled capsules and wire nuts when splicing your additional boundary wire.