All welded aluminum, will not rust. T-Bar style shelf allows for air flow. Dries pots and pans quickly. Heavy-Duty Tube Frame, 2-1/8-inches Wide T-Bar Slides. Weight Capacity is Determined by Wall Anchors, hardware not included. Stainless steel pot hook measures 1/4-inches diameter by 2-1/2-inches width by 3-3/4-inches height.