Unison™ toner: Essential to Lexmark print system performance, Unison™ toner's unique formulation consistently delivers outstanding image quality, ensures long-life print system reliability and promotes superior sustainability —all in an innovative shake-free print system. Best together: Genuine Lexmark supplies are engineered to work best together with your Lexmark printer, delivering excellent print quality from the first page to the last. Lexmark Cartridge Collection Program. Lexmark Return Program Cartridges.