Solid plastic design is spill- and tear-proof for durability Perfect for use as the back to clear front covers (sold separately). Office Depot Binding part of a large selection of office supplies. Office Depot(R) Brand Binding Backs, 8 3/4in. x 11 1/4in., Black, Pack Of 25 is one of many Binding Covers available through Office Depot. Made by Office Depot.