Two U-shaped double riveted cross braces. Features 18-gauge 0.88' round tubular frame. Double hinges for added stability and durability. Unique full size double contoured back and waterfall seat. Scotchgarded fabric is rated to 30,000 double rubs. Powder-coated frame. Color coordinated V-tip stability plugs and polypropylene glides. Fabric and foam are Cal 117 Rated. Institutional grade fabric over 1.25 in, 0.9 lb density foam seat and 1.2 lb density back. Tested by Bureau Veritas to support 500 lbs static load capacity.