The SportDOG 500 ft. Boundary Wire Accessory kit allows you to expand the range of your SportDOG pet containment fence. If you have a new pet to contain, moved to a new place with a bigger yard, or just want to give your existing pet more room, this kit allows you to do that. The 500-foot roll of standard 20-gauge, stranded copper boundary wire lets you add up to 1/3 of an acre to the existing containment boundary . This wire kit is compatible with all SportDOG pet containment fences. System includes: 500 ft. stranded copper wire. (Wire only - training flags not included with this kit)