PetSafe Boundary Wire, 500 foot Spool of Solid Core 20-Gauge Copper Wire, In-Ground Pet Fence Wire, Colors May Vary EXPAND YOUR EXISTING IN-GROUND FENCE - 500 feet covers approximately 1/3 of an acre PERFECT FOR MOST IN-GROUND FENCE INSTALLATIONS - solid core 20 gauge copper wire is rated for direct burial For proper performance we recommend using Gel-filled Splice Capsules and wire nuts (RFA-366) - SOLD SEPARATELY 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