Canon VarioPrint 6000 Series Operation Manual page 314

Add staples
5. Push the staple cartridge into the cartridge holder until the cartridge clicks into place.
[116] Firmly push the staple cartridge into the holder
6. Remove the paper ribbon that secures the staples in the staple cartridge.
[117] Remove the paper ribbon
7. Close the lower cover.
8. Place the cartridge holder in the stapler.
314 Chapter 12 - Maintain the print system
VarioPrint 6000 line