Canon imageRUNNER 6570 Reference Manual page 537

1
Open the front cover of the finisher.
The Optional Saddle Finisher-T2
2
Lift and pull out the staple case from the stapler unit, holding
it by its green tab.
3
Push down the tab on the staple case.
The Optional Finisher-T1
Clearing Staple Jams
9
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