Compatible Toner Cartridge For Samsung SCX-4521FG provides high quality compatible & OEM printer cartridges & supplies for the Samsung SCX-4521FG. Our compatible and OEM SCX-4521D3 Toner Cartridges are guaranteed to meet or exceed the factory cartridge specifications, and are backed by our Lifetime Cartridge Warranty. We also carry a full line of OEM cartridges backed the the original manufacturers one year warranty.