Outdoor Stackable Armchair KFI Outdoor Stackable Armchair - Aluminum This collection of outdoor stackable Armchairs is great for bistros, patios, poolside seating and other outdoor seating areas. Lightweight aluminum frame for strength and corrosion protection. Legs include nylon glides for stability. Chairs are stackable up to 12 units high for compact storage. Aluminum Chair has a 1" tubular anodized aluminum frame with grooved aluminum seat and back. 1 Year Limited Warranty.