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Hewlettt Packard C8054A Duplex Unit fot Printing on 4100 Series
Amazon.com The Hewlett-Packard 4100 series printers are designed for businesses that require performance and flexibility. As your enterprise grows you'll find plenty of options for expanding your printer's productivity--from envelope sheet trays to a duplexing unit. The HP duplex unit expands the printer functions to two-sided printing on a large range of media types and sizes. The duplexing unit also provides distinctive features for booklet printing. Adding the easily installable duplex unit to your 4100 series printer will allow your office to better handle the production of reports, sales packets, and training manuals, for savings through reduced paper consumption and labor. From the Manufacturer The auto-duplex attachment for the LaserJet 

Price is $155.00
Price: $155