For the following:
Samsung SCX-4500A Mono toner cartridge 2K page yield at 5% coverage
Samsung SCX-4500
Regional compatibility: EXP

Your toner cartridge will shut down at every cycle of 2K printed pages, leaving you unable to print, even though there may be plenty of toner left in the cartridge.
Slash printing costs by simply replacing the chips which shut the cartridges down, to extend toner cartridge life by up to 30-40%, or use the chip if you are refilling the cartridges, to get them working again.
Each chip lasts for one cycle of 2K printed pages, after which it must be replaced.

Some toner cartridges are region specific. If there is a region code in the description, please make sure that it matches the region of your toner cartridges. If there is no region code,,” then the chips are not regional and will work anywhere in the world. If you are not sure, please check your toner cartridge model matches the one in the description, or send us a question.”)