Give your little dog a big play area. With the Elite Little Dog In-Ground Fence?, you can contain your pet in up to 1/3 acre or even up to 25 acres with additional wire. In-ground fence systems work with buried wire around the perimeter of your containment area. The transmitter sends a signal to your little dog?s receiver collar, and gives a warning tone and a safe, static correction if he tries to cross his boundary. Your pet will soon learn his limits and enjoy the freedom of his outdoor play time.