The 700DI developer unit is another essential part of your colour laser printer, and such an important piece deserves original Lexmark quality. Designed to work with the black Lexmark Unison toner powder, the 70C0D10 gives the very best results when combined with a genuine toner cartridge.Lexmark have taken full advantage of their \"Shake Free\" system when designing this black developer unit and as a result, prints from the 700DI shine as a result. If the above selling points were not enough, the 70C0D10 black developer unit is also part of the \"Lexmark Cartridge Collection Program\" for the trouble free collection of the units once they have been fully used.