What type of blade is used and how do you change it?

Hello,  This cutter uses Blade # 45, our item number 45.60. Changing blade: Use the locking key to unlock the blade change mechanism (“lock open”). With two fingers, disengage the blade holder and swing it open. You can now lift up the blade cover to either rotate or change the blade. Finally, close the blade cover and push the blade holder back into
the handle. With a click, everything is in place. Important: To ensure your product always functions flawlessly, regularly remove any impurities.  Thank you