This specific composition offers a synergistic effect: the high aluminum content forms a durable, stable barrier layer to resist long-term corrosion, while the zinc component provides sacrificial protection at exposed edges and scratches, effectively self-healing minor damage. This dual protection mechanism results in a material with superior corrosion resistance and durability compared to standard galvanized (zinc-only) steel. It's widely used in construction, especially for roofing and siding, under standards like ASTM A792 and JIS G 3321.