Canon imagePRESS C1+ Reference Manual page 471

2
Grip the saddle stitcher unit by its handle, and pull it out of the finisher
until it stops.
3
Pull the stapler unit of the saddle stitcher unit towards you, and then
push it up.
4
Pull out the empty staple cartridge, holding it by its left and right sides.
Finisher-AA1/Saddle Finisher-AA2/Punch Unit-L1/N1/P1 (Optional)
Saddle Stitcher Unit
Stapler Unit of the
Saddle Stitcher Unit
7
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