SportDOG Static Correction Dog Fence System Pro-Grade Extreme Package What Is Included: 1 SportDOG Transmitter, 2 Waterproof Receiver Collars with both short and long contact points and batteries, 1 high-quality Surge Protector, 1,000 ft. of sturdy, 14-gauge eXtreme Dog Fence Wire, 50 ft. of 16-gauge eXtreme Twisted Wire, 10 qty.6-inch Landscape Staples (11 gauge), 2 Wire Splice Kits (waterproof), 100 Flags to mark your boundary, and a Training & Installation Manual. We also provide professional phone support to make your installation successful. Amount of Dogs: This kit is comes complete with everything you need for two dogs. With the purchase of additional collars, you can add any number of dogs. To add extra collars, please refer to the product description for a list of collars compatible with this system. Coverage Capability: This is the ONLY underground dog fence system that is designed to cover up to 100 acres of land. This hard-working system was crafted for strength and longevity. Its transmitter lets you change frequencies, so that you can avoid any possible interference with a neighboring dog fence. This SportDOG system is also compatible with the PetSafe Indoor Pet Barrier (Model # PIRF-100). Highlights: Included waterproof collars have 5 correction levels, and are designed for dogs that weigh between 20 and 220 pounds. Both audible and vibration warnings are included. The collar operates on a standard 9-volt battery. The transmitter has multiple frequencies for you to choose from. Area Coverage: This kit comes with enough wire to cover up to 1 acre of land. With the purchase of additional wire, the system can cover up to 100 acres.