The topic refers mainly to third world countries, as in developed countries, printing equipment manufacturers have points for exchanging used cartridges.
Private traders who refill cartridges often do not fill the hoppers with toner, so there is a situation when the same cartridge can print for more than a month, and sometimes only a few pages; at the same pace and filling pages.
Data will be updated for clarification.
Cartridge model Weight empty grams Weight full grams Note
Brother 2335 423 513 Without reset gears
423 518 With reset gears
Analog HP 12A 587 694