This 1.5" deep 12x12" Press-Printed Square Proof Box from Print File is double the thickness of standard proof boxes and provides non-archival storage for your 12x12" books or prints. It is made from a rigid .058" caliper board and has a separate lid and base. Featuring a "crush" embossed kraft paper exterior and a lined interior, it has a sturdy construction and is useful for book or print delivery.