This 8 foot bench with back is made of 2 3/8 inch O.D. galvanized tube with 1 1/16 inch cross brace for stability. The seat and back is made of fiberglass built with reinforcing core type construction. To guard against up ending or tipping, end overhang is only 6 inch. These benches are perfect for indoor or outdoor use. These commercial benches can be found in schools, parks, and HOA communities. Fiberglass is commercial grade and low maintenance.