Bankers Box R-KIVE Heavy-Duty Storage Boxes, FastFold, Lift-Off Lid, Letter/Legal, Case of 12 (00725) Heavy-duty, triple-end, double-side, double-bottom construction stacks up stronger and withstands frequent handling. Fast fold quick and easy assembly. Reinforced, tear-resistant handles make box comfortable to carry. Deep, locking, lift-off lid stays in place for secure file storage. Smooth rolled edges add strength and prevent paper cuts.