IWC Schaffhausen Spitfire UTC Mode D'emploi page 20

Technical refinements of the Spitfire UTC
Your IWC watch shows you the date and the time in hours,
minutes and seconds. The mechanical movement with
automatic winding is equipped with 23 jewel bearings
(synthetic rubies) and has a power reserve of 42 hours
when fully wound. A rotating 24-hour display shows you
the actual UTC time or the actual time of day in any de-
sired time zone. As you pass through a time zone, you can
adjust the hour hand of your watch in steps without stop-
ping the mechanical movement (Time Zone Corrector =
TZC). The date change is also taken into account in this
adjustment. Your Spitfire UTC has a double case; the soft
iron inner case ensures optimal protection against mag-
netic fields. Your Spitfire UTC is water-resistant to a depth
of 60 metres (6 bar). It is protected by a sapphire glass of
hardness grade 9, which is secured against displacement
from a drop in air pressure at extreme altitudes. To ensure
that this extraordinary watch continues to perform its
tasks in future, it is essential to follow a few important
operating instructions.