Frequently Asked Questions
Which two codes should I match before opening the box?
Check the label on the box against the cartridge coming out of your machine. Both should read 370AR011, also sold as TK-421. When the pair of codes on the new unit matches the pair on the old one, you have the correct cartridge and can break the seal.
Is this a full-size cartridge or a smaller starter unit?
It is the full-size cartridge, rated at 15,000 pages of black output. There is no reduced-capacity starter version in this listing — the single unit you receive carries the complete 15,000-page rating for the KM-2550.
We only change toner a few times a year. Will a spare keep on the shelf?
Yes. Kept sealed in its bag, indoors at normal room temperature and away from damp or direct heat, a cartridge stays ready for a long time. Buy it when the machine first warns of low toner and it will sit patiently until the change is actually due.
How involved is the changeover on this class of machine?
It is a few minutes of work with no tools and no technician. Open the front cover, lift the spent unit out, rock the new cartridge gently side to side to loosen the toner powder, slide it home until it clicks, and close up. The copier is ready to run again straight away.
The first copies after fitting look washed out. What now?
That is normally just settled powder after shipping and storage. Remove the cartridge, rock it gently from side to side several times, refit it, and run a short batch — density usually evens out within the first few pages. If it stays faint, contact us while the unit is still nearly full.
What cover comes with a single cartridge like this?
Every unit is backed by a 1-year warranty and 1-year free returns. If it arrives damaged or gives up early, we will put it right — our support team is available Monday through Friday, 9 AM to 5 PM CST.
What does one page cost with this cartridge?
At $81.89 for a cartridge rated at 15,000 pages, the TK-421 works out to roughly 0.55 cents per page on standard test coverage. Dense real-world output nudges the true figure up a little, light text work pulls it down, but as a budgeting number for a KM-2550 it is dependable: a copier running 3,000 pages a month spends under seventeen dollars a month on toner at that rate.
What kind of work eats into the 15,000-page rating fastest?
Pages with heavy black coverage. The rating is measured on standard test pages, and a sheet carrying dense forms, solid shaded bands or bold graphics can use several times the toner of a plain letter. A KM-2550 that spends its days on light correspondence will approach the rating; one fed a diet of dense documents all day will finish the same TK-421 noticeably sooner.
How can I tell the cartridge is really empty, and not just warning me?
Use the remedy first: if copies wash out, rock the cartridge gently side to side and run a short batch, as settled powder often explains it. When that no longer restores density — when ordinary text copies stay pale copy after copy — the toner is genuinely spent and the change is due. Fading that returns within days of rocking a nearly new cartridge is a fault, not an empty, and is worth a call to us.
What should happen to the spent cartridge?
It goes into the packaging the replacement arrived in, so residue stays contained, and from there to recycling or disposal through your local channel — not loose into general office waste. If the TK-421 is coming out early because it failed rather than because it emptied, keep the unit itself until the warranty conversation is finished; replacements are arranged cartridge by cartridge.
About This Kyocera TK-421 Black Toner Cartridge (Single)
This single compatible black cartridge — order code 370AR011, known as TK-421 — is the plain one-off replacement for a KM-2550 that has just run dry: one machine, one cartridge, no stockroom arithmetic. It is priced at $81.89 and rated at 15,000 pages, so the next changeover stays a long way off. Orders ship from our warehouses in IL, PA, GA and CA; delivery and returns details are on our shipping & returns page, and the full Kyocera-Mita range is on the site if your office runs other models alongside it.
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