Extra boundary wire for Koolkani  KK-9000,GROOVYPETS-113FR, and Easypet EP-8000 In-ground/underground Pet Electronic Fence Dog Containment System 

May be suitable for other brand in-ground/underground electric fence systems

Gauge 23,Length: 150M/500 Feet, good for 1/3 acre.

You may calculate the wire needed for your fence system:
To Cover This Size Area             You Need This Amount of Wire
1/3 Acre                                           500 Feet
1/2 Acre                                           600 Feet
1 Acre                                             1000 Feet
2 Acres                                           1300 Feet
3 Acres                                           1500 Feet
4 Acres                                           1800 Feet
5 Acres                                           2000 Feet

FREE USPS PRIORITY MAIL for US buyers. Delivery within 2-4 days.