1.1 This specification covers 12 1/2-gage (0.099-in.) [2.5- mm] Class 3 metallic-coated steel wire suitable for use in parallel–wire fence, trellis, an This specification covers metallic-coated steel smooth high-tensile fence and trellis wire. Two types of coatings are covered; Type 1, which are zinc-coated, and Type II, which are zinc-5% aluminum mischmetal alloy coated. The material as represented b