CHRIST Christy® reinforced concrete enclosures are reliable and cost effective. Sycamore With a galvanized or black finished 1/2 inch steel cover and steel seat ring cap in place, these boxes are traffic rated. Body: Concrete Lr Cover: Concrete is F. R-Series & F-Series Composite Lid + High performance composite ld with patented reinforced polypropylene ring combined with concrete. Prevents chipping, cracking, and ensures cover fit and longevity.