Standard slots have been truncated with triangles to form a subtle diamond shape and the border has small triangle depressions, giving the piece a classical air. Conforms to ADA Accessibility Guidelines. AVAILABLE MATERIALS: 100% Recycled Grey Iron, Ductile Iron, 100% Recycled Aluminum, Silicon Bronze, Nickel Bronze. AVAILABLE FINISHES: Raw Natural Finish, Rust Conditioner (Grey and Ductile Iron Only), Polyester Powder Coat, Liquid Coat (Available upon request), Brush (Aluminum, Bronze and Nickel Bronze Only), Polish (Aluminum, Bronze and Nickel Bronze Only).