This listing comes with an additional collar for the system The Wireless Pet Containment System™ keeps pets happier while you breathe easier. A simple signal from a small unit in your home to your dog’s collar is all it takes. They learn their new yard boundaries quickly and comfortably, and the collar will remind them with a tone or static correction if they forget. Before you know it, it’s all happy playing and no random straying. Covering an area up to ½ acre, it’s portable, requires no buried wires, and sets up in 1-2 hours. Features For dogs 8 pounds and up Fits neck sizes 6-28 inches 5 adjustable levels of static correction Tone-only mode alerts your pet with a beep Automatic safety shut-off: correction stops after 30 seconds Covers an adjustable circular area up to 1/2 acre (180 feet in diameter) Expand containment size with additional wireless transmitters Add an unlimited number of pets with additional wireless receiver collars Waterproof receiver collar Collar uses PetSafe RFA-67 battery (included) Also works with Stay + Play Wireless Fence and Stay + Play receiver collar Moving & Wont be able to use it. Make me an offer Local pickup only