PetSafe Free to Roam Wireless Fence Receiver Collar ADD UNLIMITED PETS TO YOUR SYSTEM - keep as many pets as you need safely in your yard as long as they wear a PetSafe Wireless Fence Receiver Collar (Not compatible with PetSafe In-Ground Fences) WATERPROOF RECEIVER COLLAR - for all of your pet's outdoor activities 4 LEVELS OF STATIC CORRECTION - customize to your pet's temperament. Also has a tone only mode for training. SLIM, ERGONOMIC DESIGN - fits pets 5 pounds or more with neck sizes 6 to 28 inches SHORT AND LONG CONTACT POINTS INCLUDED - for pets with long or short hair BATTERY INCLUDED - Operates with RFA-67D-11 battery module; expected battery life is between 1-2 months Call, chat or email with our expert PetSafe US-based customer care specialists six days a week; They are waiting to assist you and your pet with your product needs at 1-800-732-2677 or by email at ccc3@petsafe.net Manufacturers warranty is only valid when purchased from an authorized retailer