Thanks for joining the conversation, Robert60!
Your Canon printer's model number should be displayed prominently on the top and/or front of the unit. Our model numbers typically begin with letters (such as G, GX, TS, TR, MX, MG, MB, MF, MP, LBP, iP, or iX) followed by up to 4 numbers. We do not have a printer model number of TR7422, possibly TR4722 is what you are referring to?
We hope this helps!
