Let all of your pets enjoy more outdoor freedom! Add an unlimited number of pets to your YardMax in-ground system with this PetSafe® YardMax® Rechargeable In-Ground Fence™ Collar. YardMax® maximizes the amount of yard space for your pet to play freely in. When your pet nears the boundary, the collar will give a warning beep, followed by a static correction to remind your pet to stay within the boundaries. Your pet will be enjoying greater yard freedom in no time!