LD Compatible Toner Cartridge Replacement for Samsung SCX-4521D3 (Black) Page Yield: 3,000 | Shelf Life: 24-36 months We offer lightning fast shipping on all printing supply and inkjet photo paper orders The use of LD replacement ink and toner cartridges does not void your printers warranty All LD branded products are backed by a 100% satisfaction and LIFETIME guarantee For use in the following Samsung SCX printers: SCX-4321, SCX-4521, SCX-4521F, SCX-4521FG, and SCX-4521FR