Garmin G500 Pilot's Manual page 82

Nav Range Ring
When turned on, the Nav Range Ring option will show a ring with a compass
rose around your present position on the Navigation Map. The relative size
shown on the map will remain the same (25% of the map range).
Figure 3-26 Navigation Map Range Ring Selection
3-18
Figure 3-25 Navigation Map Range Ring
Garmin G500 Pilot's Guide
Range Ring Radius
Range Ring with Compass Rose
190-01102-02 Rev. B