Super strong boxes can be stacked up to six high. • Heavy duty, triple end, double side, double bottom construction stacks up stronger and withstands frequent handling • FastFold™ quick and easy assembly • Reinforced tear-resistant hand holes 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 • Boxes feature a write on area on two sides for labeling with content information. • Sold in case quantities.