Classroom Keepers 10-Slot Mailbox, Blue (001309) Store and organize classroom materials, designed with an individual name tab on each slot The slot sizes for the 10-Slot Mailbox are 3 inches high x 10 inches wide x 12-1/2 inches deep The whole unit measures 16-5/8 inches high, 21 inches wide and 12-7/8 inches deep Sturdy corrugated boxes are made from recycled material and are recyclable Can be mixed and matched with Pacon's 15-slot and 30-slot mailboxes to fit your needs