The 8 Bin Mailbox for HP LaserJet printers adds eight 250 page output bins for easy access to print jobs. HP 8-bin Mailbox for HP LaserJet Printers 8100, 8000, 8550dn, 8550gn, and 5si series printer; adds 8 bins, 2,600 total capacity, four intelligent operating modes: Stacker, Mailbox, Collating, Job separation