The PetSafe Stay and Play Wireless Fence System is a great way to safely give your furry friend freedom in the backyard. The PetSafe Stay and Play wireless fence requires about one to two hours of setup time to create a circular boundary up to 3/4 of an acre. The electronic dog collar offers five levels of static stimulation as well as tone-only mode depending on your dog's temperament. For added convenience, the PetSafe Stay and Play wireless fence is portable for use while camping or at someone else's house. If you have more than one pup, this wireless fence system is expandable with the purchase of additional collars. Make sure your dog can safely have fun outdoors with the PetSafe Stay and Play Wireless Fence System. Features:Specs:Includes:Compatible Add-a-Dog wireless receiver collars include: