PetSafe Wireless Pet Containment System Receiver Collar Only for Dogs and Cats over 5 lb., Waterproof with Tone and Static Correction - From The Parent Company of INVISIBLE FENCE Brand

PetSafe® Wireless Pet Containment System Add-A-Dog® Extra Receiver Collar can be used to either add another dog to an existing Wireless Containment System or as a replacement collar. You can add an unlimited number of pets to your containment system as long as each pet has a compatible receiver collar.