The PetSafe® Little Dog In-Ground Fence™ allows little dogs have the freedom to play while staying safely in their yard. Simply bury the wire where you wish your boundary to be. Your dog wears a receiver collar that detects the radio signal travelling through the wire. When your dog approaches the boundary, the receiver will issue a warning tone. If your dog ignores the tone and tries to cross the boundary, he will receive a safe, but startling, static correction. While harmless, the correction will persuade him to stay in the established containment area. With 4 levels of static correction plus a tone only mode, you will be able to select the right level for your dog. Trust PetSafe® to help keep your pet healthy, safe and happy. Features In-ground fence for small dogs 5 lb and up Includes 500 ft of wire to fence in a 1/3-acre yard Expandable up to 25 acres — just purchase as much extra wire as you need Battery-operated collar uses 1 RFA-188 battery, included Collar has 4 levels of adjustable static correction plus a tone-only mode for training Purchase additional receiver collars for every pet in your family Waterproof Fits neck sizes 6-16 in Compatible in-ground fence collars: Little Dog In-Ground Fence™ Receiver Collar Deluxe UltraLight™ Receiver Collar Rechargeable In-Ground Fence™ Receiver Collar Stubborn Dog In-Ground Fence™ Receiver Collar In-Ground Fence™ Receiver Collar for Cats Formerly known as the Elite Little Dog In-Ground Fence Our static collars are part of our ongoing mission to provide the best tools, education and support for pet parents seeking safe, effective, expert-recommended options they can trust to meet each dog’s unique training needs