Paxar Monarch 9855 RFID Printer - Manual (Page 30)

11. Rotate the take-up core until the leader is past the printhead.
12. Remove any slack in the ribbon by turning the take-up reel
clockwise.
13. Hold the printhead assembly by the printhead tab while
pressing down on the printhead release.
14. Close the printhead by pressing down on the thumb well until
you hear it click into place.
15. Close the cover.
Thumb Well
3-4 Loading Ribbon