Description : FEL00051 Extra Strength For moderate use and higher stacking needs. Medium-duty construction for higher stacking or for use with shelving. Easy one step FastFold set up. Attached flip-top lid for moderate storage security and no missing lids. Box Type: Storage; Global Product Type: File Boxes; Box Style: N/A; Material(s): 2 Ply Bottom; 2 Ply Side; 3 Ply End.