PET SAFE BOUNDRY WIRE Expands your containment system beyond the initial 500 feet of wire that accompanies the in-ground fencing kit. Each spool contains 500 feet of 20 gauge, solid core, burial-grade wire. For proper system performance, the splice connection must be waterproof. We recommend using Gel-filled Splice Capsules and wire nuts (RFA-366) when splicing your additional Boundary Wire. Compatible with PetSafe or Innotek in-ground fence kits To determine how much wire is need, use the information below. Keep in mind that creating interior loops to boundary off areas like gardens and swimming pools will require more wire. (Information assumes square layouts, rectangular layouts may require more wire.) 1/4 acre, 415 feet of wire (1 kit needed) 1/3 acre, 480 feet of wire (1 kit needed) 1/2 acre, 590 feet of wire (2 kits needed) 1 acre, 835 feet of wire (2 kits needed) 2 acres, 1180 feet of wire (3 kits needed) 5 acres, 1870 feet of wire (4 kits needed) 10 acres, 2800 feet of wire (6 kits needed) 25 acres 4500 feet of wire (9 kits needed)