These Canon toner cartridges are suitable for Canon i-SENSYS LBP printers, such as the Canon i-SENSYS LBP623Cdw and the Canon i-SENSYS LBP621Cw. Note that not every toner cartridge fits in every printer. Which toner cartridge you should buy, depends on your printer. Check which printer model you have. You can find this on the front of your printer or in the manual. On the product page, you'll find a list with suitable printers, so check if your printer is on it. This way, you always buy the right toner cartridge for your printer.