THEY ARE PRODUCED BY A DIFFERENT SUPPLIER THAN THE "NON ECO" SERIES. 12 MONTH WARRANTY! Oki C 5600N, 5600DN, 5700DN, 5700N Compatible Printers. ECO SERIES COMPATIBLE CYAN TONER C5600 FOR OKI C 5600N 5600DN 5700DN 5700N 43381907 CAPACITY 4,000 PAGES.
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