Offering the five-inch Commercial Box Gutter System in 24-Gauge Galvalume®. Galvalume® is projected to outlast galvanized steel in various atmospheres by up to nine times. Galvalume® is an aluminum-zinc alloy coating used for gutter applications because of its corrosion resistance properties and long term durability. Galvalume continues to gain approval by specifiers, architects, building owners and many others due to its versatility, ease of use, aesthetics and performance. Browse here for gutter, downspout and matching components in Galvalume®.