The Delta-13 Elite Ball Rack is a great piece of craftsmanship and design. The Rails and Corners are made from 100 billet aluminum. The corners and rails are fastened with 4-40 stainless steel screws that are secured with high strength loctite 262. The rails have a color anodized coating while the corners have a clear anodized finish. Every rack is measured by a coordinate measuring machine to ensure exact tolerances.