Some cartridges are compatible with over 30 printers and therefore there isn't enough room to list all printers on the packaging.
I appreciate it doesn’t help when you receive your cartridge but a quick way to check its compatibility is simply looking at the number on the old cartridge and comparing it with the new one.
If you are unsure, please contact Customer Services before opening the item and they will be happy to check for you. Please ensure that you have your printer model to hand when contacting as this will allow them to check the compatibility for you.