Canon Color ImageRunner C3380 Reference Manual page 381

NOTE
Only one staple cartridge can be inserted at a time.
5
Remove the seal holding the staples together, by pulling it
straight out, and then down.
IMPORTANT
Make sure you pull the seal straight out, and then down. If you pull it out at an
angle, it may tear.
6
Gently push the staple case into the finisher until it is securely
in place.
7
Close the front cover of the finisher.
Finisher-Z1 (Optional)
7
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