IWC Schaffhausen PORTUGIESER TOURBILLON RÉTROGRADE CHRONOGRAPH Mode D'emploi page 18

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T H E T E C H N I C A L R E F I N E M E N T S O F T H E
P O R T U G I E S E R T O U R B I L L O N
R É T R O G R A D E C H R O N O G R A P H
Your IWC watch shows you the time in hours and minutes and the
retrograde date. You can use the integrated flyback chrono graph
to measure any period of time in seconds, minutes and hours.
Stop times can be added together. The mechanical movement
with automatic winding has a power reserve of approximately
68 hours when fully wound. Your Portugieser Tourbillon Rétrograde
Chronograph is protected by an arched-edge sapphire glass of
hardness grade 9 on Mohs' scale. Your watch is water-resistant
3 bar. Your watch is also equipped with a flying hacking minute
tourbillon. The hacking tourbillon has two spring arms that en-
able timing with down-to-the second accuracy. The tourbillon, an
invention made in the aftermath of the French Revolution, has
always been regarded as the ultimate challenge in the quest for
absolute mechanical watchmaking precision. More specifically,
the purpose of the mechanism is to counterbalance the one-
sided pull of the earth's gravity on the balance. This is because
the residual gravitational error of the balance influences the ac-
P O R T U G I E S E R T O U R B I L L O N R É T R O G R A D E C H R O N O G R A P H