If you need an extra collar for a canine companion in your family, then this PetSafe Wireless Fence Receiver Collar is the paw-fect choice. This add-on collar can be used to either add another dog to an existing wireless containment system or as a replacement collar. This collar helps keep your furry friends contained in your yard, where they can safely rest and play. You can add an unlimited number of paw-tners to your containment system—simply purchase a compatible receiver collar for each pet. This waterproof collar comfortably fits small, medium, and large furry friends who weigh 8 pounds or more. It adjusts to fit neck sizes 6-28 inches and is compatible with all PetSafe Wireless Fence Transmitters. Plus, with this collar, you can personalize the settings, use the tone-only training mode, or choose from five levels of static.