View the selection below to find the printer cartridges that are to suit the Oki MB491 printer. When purchasing replacement cartridges for your Oki MB491 printer, whether that be ink cartridges or toner cartridges, they are separated into two different kinds. There original cartridges or genuine cartridges which are known as OEM cartridges, as they are supplied by the manufacturer that makes the printer/copier/inkjet printer. An alternative to the brand named genuine cartridges, for your Oki MB491 printer are also compatible cartridges which are sometimes also referred to as generic cartridges, for your printer ink cartridge or toner cartridges supplies. In most circumstances these are still brand new cartridges (in some instances remanufactured) and these cartridges are a much more economical choice and will save you money on your printing expenses.