I am writing this review to clarify something about this cartridge model as the photo is a bit deceiving so I have done some research to avoid doing the same mistake in the future or at least confirm I know what I am buying.
1. It is not the same size as in the picture, it is half the width, similar to the normal cartridge but with more ink. In fairness to whoever is selling this cartdrige with the wrong picture, the HP website also shows this picture.
2. It does say XL in the box and on the cartdrige but this model is the CN684EE ABB (550 pages) that replaced the original XL high capacity (big cartridge, 800 pages) model CB321EE, which funny enough some sites show with a small picture just to make it even more confusing :).
3. I found one of those refurbished ink sellers answering a lot of questions about this cartridge,[...]
or just search somewhere for "New Smaller Body for HP 178, 364, 564, and 862 Black XL Ink Cartridges" to get the HP official version and to understand more about the changes.
4.Very hard to find how many ml this CN684EE has, one site said it was 12ml. The original XL CB321EE seems to have 18ml and many refurbished cartdriges also have 18ml. I have bought one 18ml refurbished cartridge previously and it did really felt that it run for a long time compared to previous HP cartridges so from now on I will be looking for 18ml versions and test around different manufacturers until I find the "best".
I did not give it 5 stars because of the picture (it led me to think it was the bigger model, I guess too good of a price to be true) but gave it 4 because it is still an official HP XL cartridge, arrived fast and in a good condition with original packaging, the price at the moment was better compared to other sites but it would be nice to if the page had extra details explaining more about the ink and if the photo was accurate.
Hope it helps.