When it comes to high security venues such as substations, power plants, and correctional facilities, ordinary fencing will not suffice. In addition to enclosing a perimeter, the barrier must include a topmost layer armed with concertina wire. The wire should be supported via "arms" that hoist it above the top rail. This way, even if an intruder manages to scale one side of the fence, they won't be be able to climb over without getting snagged and cut by the barbs. In many cases, the barb arms are projected at a 45-degree angle, to make intrusion/escape even more difficult. What this means, however, is that you must maintain an identical barb arm angle across all points of your fence, including the corners. This is where the 3" barb wire arm comes into play. Designed to sit on the corner post of a fence, its arm projects outward in the same direction as the corner. This way you can install a perfectly rectangular barb wire top barrier.
This barb arm has been fabricated with three notches and thus can hold three strands of barb wire. The design of the notches helps prevent intruders from prying the wires free. It has also been fabricated from galvanized, rust-resistant steel. High security venues must use corrosion-resistant materials, as their fences are perpetually exposed to the elements (rain, dew, etc.). Even a small weakness brought on by rust can lead to a security breach. This barb wire arm is designed for 4" posts and adds an addition twelve inches of height to your fence.