iwc GROSSE INGENIEUR CHRONOGRAPH Mode D'emploi page 16

The technical refinements of the Big Ingenieur Chronograph
Your IWC watch shows you the time in hours, minutes and seconds, to-
gether with the date. You can use the integrated chronograph to measure
any period in seconds, minutes and hours. Stop times can be added
together. The mechanical movement with automatic winding has 40 jewels
(synthetic rubies) and a power reserve of approximately 68 hours when
fully wound. Your Big Ingenieur Chronograph is protected by sapphire
glass of hardness grade 9 on the Mohs' scale. Your watch is water-resistant
12 bar. To ensure that this extraordinary watch continues to perform
faultlessly in the future, it is essential to observe a few important operating
instructions.