CS-S4521) BK compatible toner cartridge For samsung scx-4521d3 scx-4321 scx-4521 scx-4321f scx-4521f (3k pages) - AliExpress
How to remove and re insert the Toner of Samsung SCX-4521F Printer - YouTube
SPS 4521 / SCX4521 Black Toner Cartridge for Use in Samsung SCX-4521, SCX-4321F, SCX-4521F, SCX-4321 Single Color Toner (Black) : Amazon.in: Computers & Accessories
Amazon.com: greencycle Compatible Toner Cartridge Replacement for Samsung SCX-4521D3 SCX4521 Use for SCX-4521 SCX-4521F SCX-4521FG SCX-4521FR SCX-4321 SCX-4321F Printer (Black, 1-Pack) : Office Products