Keeps your letter/legal file boxes accessible during temporary storage. Flip the lid and place the box inside it for frequent, easy access to files. Modular shell with steel support, stacks five units high to save floor space. Eliminates the need to stack or re-stack boxes. Durable shells with wire frames clip together vertically and horizontally for stability. Features Quick Set-Up assembly. Box Type: Quick Set-Up; Material(s): Corrugated; Strength: Heavy-Duty.