The key to an effective tension fence is high-tensile wire that is able to withstand constant fence tension, as well as tension increases due to animal impact or cold-weather contraction. While all high-tension fences are constructed of high-tensile wire, not all fences made of high-tensile wire are high-tension fences.
“High-tensile” refers to the wire’s strength. “High tension” refers to its tautness—great enough so that the wires can’t be easily pried apart and will bounce back on sudden impact. Instead of bouncing back, low-tensile wire (called “soft” wire because it contains less carbon and is therefore physically softer), stretches and breaks in similar situation