Some Canon and HP laser printers take universal cartridges that fit both brands. You may in some circumstances order remanufactured Canon toner cartridges and receive items labelled as HP compatible.
For example, the Canon 718 range of cartridges is often labelled as HP304 or CC530-3.
You can find out if the cartridges you have received are universal equivalents by typing both numbers into the same Google search (in the example above you could search "Canon 718 HP 304" or "718 CC530" etc). If you see a lot of listings showing them as the same product, you can safely assume that you should open the box and use the toner.
If you're not sure, or would like us to verify that you have the right cartridges, just contact us with your order number and we'll check for you.