Garmin GPS 12 MAP Owner's Manual page 104

Landmark Log:
Use this space to record Landmarks that you
want to retain for use in the future, but are
deleting from the waypoint list contained in
the GPS 12 MAP to make space for new,
more active waypoints.
No. Description
9 4 4 9
Record your unit Serial No.
________________________
to speed recovery if lost or stolen and for
warranty service.
Notes:
Use this space to record notes about each
Lat/Lon
landmark, such as date, description, etc.