Extend your electronic fence boundary an extra 500 feet Suitable for use with any brand electronic fence Solid copper core Extra high-strength insulation Resistant to sunlight, moisture, ground rot Resists breaking Model BE-500 Expand the coverage of your electronicfence. Boundary Extension Kit gives you 500 feet of customengineered Ultra Wire'„¢, 50 boundary flags and 5 waterproof wiresplices. This wire is specially engineered for electronic dogfences with electrical and mechanical properties optimized for yourdog containment application. The wire is solid-core copper designedfor optimum electrical impedance. It has an extra thick jacket madeof a specially formulated insulation material that is resistant toultraviolet sunlight, moisture, ground rot and corrosion. Hightensile strength insulation greatly reduces the risk of wirebreaks. Whether you have a genuine Humane‚® Contain electronic dogfence or another brand, this is hands-down, the best dogcontainment fence wire you will find anywhere. High Tech Pet Boundary Extension Dog Containment Kit, Size: 1 Count | PetSmart