Proper containment is essential. Responsible pet ownership starts with keeping your pet safely at home. PetSafe's In-Ground Radio Fence Pet Containment Systems provide your pet with freedom and safety while costing thousands less than conventional fencing. It's quick and easy to install, reliable and safe, and with proper training, a very effective solution. How Radio Fence works: A transmitter plugs into a standard outlet and emits a radio signal that travels along an underground wire. A lightweight receiver is worn on your pet's collar which picks up the radio signal and alerts your pet as he nears the underground boundary. The method of correction your pet receives depends on the system that is purchased, varying from a warning tone to a mild static correction. Once your pet is properly trained he will learn to stay in the boundaries designated by your Radio Fence.