With the Neon Bubble Tester, you can quickly check your fence by simply inserting the top probe into the wire and the bottom probe into the ground—no extra tools or batteries needed. The built-in neon lights clearly show different voltage levels, helping you understand your fence’s condition at a glance. You can use it easily on all common fence materials, including metal wire, poly wire, rope, and tape—making it a perfect tool for your farm, garden, or any livestock fencing setup.