Aside from the date, day, month and year in four digits, the Portuguese Perpetual Calendar also indicates the number of days remaining until the next full moon. The display showing its course and featuring mirror images of the moon in the northern and southern hemispheres deviates from the moon's actual progress by just 12 seconds in one lunar period. The moon phase displays used in the Da Vinci Perpetual Calendar Edition Kurt Klaus are astonishingly accurate and deviate by just one day, after 122 years. The Portuguese Perpetual Calendar is even more precise. Larger moon phase wheels with different numbers of teeth reduce the deviation so drastically that a future inheritor of this watch would theoretically need to have it adjusted by only one day in 577.5 years.