The National Public Seating 1100 Series steel frame Polyfold fan back double hinge folding chair has a black, 18 gauge, 7/8" tubular steel "Y-frame" structure, black plastic seat and backrest, three double-riveted leg cross braces, double hinges on each side, and it folds for efficient storage when not in use. This chair meets the American National Standards Institute/Business & Institutional Furniture Manufacturers Association (ANSI/BIFMA) standard for drop weight support of 300 lb., and it supports 480 lb. of static weight. It has three double-riveted leg cross braces (two on the back legs, one on the front), and double hinges on each side for stability. The steel frame is powder coated for corrosion resistance, and supports the perimeter of the plastic seat for strength. A space at the top of the backrest allows the frame to be used as a handle to facilitate carrying. Replaceable polypropylene glides help protect floor surfaces. Plastic plugs at the top of the back legs have a slot shaped to hold the frame and add stability. These plugs and the floor glides match the plastic seat and backrest color. When folded, the chair fits very close to another of its kind for efficient storage, stacking horizontally up to 26 high, making it suitable for institutional temporary seating applications. The chair is Materials Analytical Services (MAS) certified as low volatile organic compound (VOC) emitting furniture according to the criteria defined by U.S. Green Building Council (USGBC) Leadership in Energy & Environmental Design (LEED) 2009 for Schools, LEED 2009 for Commercial Interiors, ANSI/BIFMA X7.1-2011, ANSI/BIFMA e3-2011e Furniture Sustainability Standard - Section 7.6.1, and the MAS Certified Green program. SpecificationsSeat size15-3/4 x 16 inches (W x D)Seat height17-3/4"Backrest size13-1/2 x 18-1/2 inches (H x W)Overall dimensions, folded44 x 18-1/2 x 2-1/4 inches (H x W x D)Overall dimensions, open34-1/2 x 18-1/2 x 20-3/4 inches (H x W x D)Weight9 lb.(H is height, the vertical distance from lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.) National Public Seating manufactures furniture and associated transport and storage accessories for educational, worship, hospitality, food service, and other institutional venues. The company, founded in 1997, is headquartered in Clifton, NJ.