The materials used in these fences are typically galvanized or powder-coated to withstand corrosion, extreme weather conditions, and environmental degradation. Their construction may also include anti-dig features, deep foundations, and seismic sensors to prevent infiltration from below. Some military-grade fences are even designed to absorb blast impacts and remain functional during hostile actions, ensuring continuity of security even under attack. Their imposing height—often 10 to 20 feet or more—serves as a visual deterrent and a psychological barrier.