Protect your dog from wandering away by demarcating boundaries with the Radio Systems SDF-100A Sport Dog 100 acre In-Ground Fence System. Simple and cost-effective, this fence system covers up to 100 acres of land. Keeping your dog well within boundaries, it transmits signals to your dog's collar, which then alerts the dog about distance. The waterproof collar has four adjustable levels of corrections in the tone and vibration mode. This system teaches your dog to remain well within your yard perimeter. Ground fence system for dog containment and training. 4 levels of adjustable correction. Features wire-break alarm on transmitter. Waterproof collar receiver. Includes 1000 ft of wire and flags.