The compendium has a single cover plate and a box. It is in unadorned style, with no engraved decoration. The cover is held in place by two clasps.
The front cover and the back plate contain the two halves of a table giving, for every second day of each month, the times of sunrise and sunset, and the lengths of the day and the night. January to June are on the front cover, July to December on the back.
On the reverse of the cover is a horizontal pin-gnomon sundial for Italian hours 10 to 23. The tropic of Cancer is marked 'TROPICVS ESTIVALIS', the equator 'EQVINOCTIALIS' and the tropic of Capricorn 'TROPICVS HYEMALIS'.
Under the dial is a circular lunar volvelle titled 'BESCHEINVNG DES MONS EIN JEDE NACHT SEINES AB VND ZV NEM:'. The fixed outer scale for the age of the moon runs 1 to 291/2, and the two inner rings give the moon's distance from the sun in hours and minutes. The volvelle has a radiating hour scale 1 to 12, 1 to 12, with half hour graduations, and a pointer at 12.
The compendium's main box carries an inclining dial, whose inclination is set by an index in a graduated slot on the forward outer edge of the box. The slot's latitude scale of degrees runs 45 to 66, divided and numbered by 3. The dial's hour plate is 4 to 12 to 8, with half hour graduations. The folding gnomon is sprung to the perpendicular.
The compass bowl lies under the gnomon, with a silvered base plate cross-marked for the four cardinal points, and marked 'SE', 'OR', 'ME' and 'OC'.