Self-winding mechanical movement. Caliber 240 LU CL C. Date by hand. Hours and minutes of mean solar time. Sky chart, phases and orbit of the Moon. Time of meridian passage of Sirius and of the moon. Blue sapphire-crystal disks for sky background and moon phases.
Dial: three metalized sapphire-crystal discs as well as ellipse framing the portion of the sky visible from Geneva.
Platinum. Case: platinum. Sapphire-crystal case back. Water resistant to 30 m. Case diameter: 44 mm. Height: 10.58 mm.
Alligator strap with square scales, hand-stitched, shiny navy blue. Fold-over clasp.