Keeps your letter / legal file boxes accessible during temporary storage. Flip the lid & place the box inside for frequent, easy access to your files. Modular shell with steel supportstacks five units high to save floor space & eliminates the need to stack or re-stack individual boxes. Durable construction with wire frames that clip together vertically & horizontally to ensure stability. Features Quick Set-Up assembly. File Box Accessory Type: Shell; for Use With: Letter / Legal-Sized Lift-Off Lid Filing Boxes; Inner Width: 12"; Inner Height: 15".