Step Action Illustration5 Squeeze at the indicated positions to re-lease the empty staple cartridge.Lift the empty staple cartridge and pullthe staple cartridge out.6 Insert the new staple cartridge (StapleP1).NOTEWhen you replace the staplecartridges, replace both thefront and back staple cartridges.7 Return the staple case to its original posi-tion in the saddle stitch unit.Make sure that the arrow on the staplecase aligns with the arrow on the saddlestitch unit.NOTEFollow the steps 3 to 7 to re-place the other staple cartridgein the saddle stitch unit.8 Gently push the saddle stitch unit back in-to the printer.9 Close the front door of the stacker/stapler.CAUTIONWhen you close the front doorof the stacker/stapler, be care‐ful not to get your fingerscaught, because this may resultin personal injury.Replace the staple cartridge of the saddle stitch unit (Staple P1)26 Chapter 3 - Use the stacker/stapler Canon Finisher-AK1/Saddle Finisher-AK2/Puncher Unit-BT1/BU1Operation Guide Finisher-AK1, Saddle Finisher-AK2, Puncher Unit-BT1-BU1: VarioPrint (VP) 110, VP120, VP135 - Edition 2013-06