This is a compatible or remanufactured Brother TN637M toner cartridge guaranteed to perform with Brother Laser Printers. It replaces the genuine (OEM) Brother TN637M toner cartridge. This toner cartridge is made with top quality components and new toner to give you the highest quality printouts every time. This compatible or remanufactured for Brother TN637M toner cartridge is specially engineered to meet or exceed the highest standards of quality, reliability and page yields. Although this cartridge is not made or endorsed by Brother, it offers customers an economical alternative to expensive OEM Brother TN637M cartridges and comes with our satisfaction guarantee.