If you are looking to run the Oki B440 (or any other compatible printer) with a genuine product, then the 43979216 black toner cartridge is for you. This original OKI 43979216 toner cartridge is estimated to offer 12,000 top quality prints, making it great value.Produced by the same folk that are responsible for your printer, the 43979216 toner cartridge works flawlessly. Although the genuine OKI 43979216 toner cartridge comes fully guaranteed, issues are so rare that it is there for your peace of mind more than anything else.