The Lexmark 50G0852 4-bin mailbox offers four output destinations and installs on the top of the printer | Supports up to 100 sheets of 75gsm paper per bin of A4, A5, A6, JIS B5, Executive, Folio Letter, Legal, Oficio or Statement sizes | Only Paper 60 to 90gsm may be used with this unit | Up to three units may be installed | Any combination of Off-set Stacker and 4-Bin Mailbox for up to a total of 3 devices may be configured | The 4-Bin Mailbox supports bin 'empty' and 'full' sensing