1.1 This specification covers round, high-strength, zinc-coated (galvanized), steel core wire with Class A zinc coating (GA3) for use in overhead electrical conductors.. 1.2 This specification covers wire of diameter from This specification covers the standard requirements for round, high-strength, zinc-coated (galvanized), steel core wire with Class A zinc coating used for mechanical reinforcement in the manufacture of special steel reinforced aluminum and aluminum-all