Patek Philippe 240 HU Mode D'emploi page 12

Each time the push piece is actuated, the hour
12
hand that displays local time advances by one
hour while the 24-hour ring and the city ring
move counterclockwise. Thanks to an ingenious
coupling mechanism, the minute hand is not
affected by this switching operation. It continues
to move forward with unperturbed precision. This
local time correction mechanism, using one single
push piece that executes three commands simul-
taneously, is an exclusive feature of Patek Philippe
World Time watches.
Correction
push piece
Hour hand
City ring
Correction push piece:
Synchronized correction of the hour
hand in one hour increments and
counterclockwise in 1/24th increments
of the city ring and 24 -hour ring.
Minute hand
24-hour ring
1 2
Position 1:
Winding
Position 2:
Setting the time