Prefabricated to meet NFHS specifications. Designed facilitate easy set up and convenient concrete pour. Structure is made specially folded 18' aluminum to maximize integrity and rigidity. This form is designed to receive the Aluminum Sand Pit Cover System . Inside Dimensions 23' x 9'9'. Please Note This item CANNOT ship to P.O. Boxes, APO, or FPO Addresses. It CAN ONLY ship to a Street Address.