Description This containment system keeps your pet safely contained and secure in your yard. Install the system in about a weekend by setting up the transmitter and burying wires around your yard. The fence covers up to 5 acres with additional wire and flags. You'll place flags around your yard and train your pet where his new yard boundaries are in fun, quick training sessions over the next 2 weeks. Most pets learn their new boundaries quickly. If your pet gets too close to the yard edge, the waterproof receiver collar reminds your pet with a warning beep, followed by a safe, gentle static correction if he continues. Add an unlimited number of pets by purchasing an extra collar for each pet.PRODUCT DETAILS: Waterproof receiver collar for dogs 8 pounds and up, fits neck sizes 6-28 inches. 4 adjustable levels of static correction or tone-only mode alerts your pet with a beep. Correction increases if your dog tries to run through the boundary zone. Collar uses PetSafe RFA-67 battery (included). Covers up to 1/3 acre with included boundary wire, expandable up to 5 acres with additional wire (not included). Add an unlimited number of pets with additional in-ground receiver collars. WHAT'S INCLUDED: Transmitter with power adaptor, receiver collar with RFA-67 battery, short and long contact points for short-haired and long-haired pet, (50) boundary training flags, 500 feet of 20-gauge boundary wire, surge protector, test light tool, wire nuts, waterproof gel-filled wire splice capsules, product manual.