Portugieser Constant-Force Tourbillon Double Moon Platinum / Silver

In Context

At 46 mm it is a large watch — well above this catalogue’s 40 mm median, and enough to dominate a narrow wrist. At 13.4 mm it is a tall case, and it will catch on a cuff. The case back is open, so the movement is visible without taking the watch apart, and the sapphire crystal will resist everything short of deliberate abuse. Rated to 30 m, it is protected against rain and splashes and nothing beyond that.

The movement is hand-wound, so winding it becomes part of the day rather than something the watch does for you. 96 hours of reserve puts it well past a weekend — several days off the wrist and it is still going. At 18,000 vph the seconds hand advances 5 times a second, the slower and more audible rate of an older design.

IW5901-05 is one of 10 executions of the IW5901 base reference. Underneath they are the same watch; what separates this one is a silver sunburst dial and a platinum case. It was a limited edition. Beyond the time it carries a tourbillon.

IWC

Grey · Red Gold

IW5901-01 · 46 mm

IWC

Grey · Platinum

IW5901-02 · 46 mm

IWC

Blue · Platinum

IW5901-03 · 46 mm

IWC

Black · Platinum

IW5901-04 · 46 mm

IWC

Blue · Red Gold

IW5901-06 · 46 mm

IWC

Black · Red Gold

IW5901-07 · 46 mm

IWC

Silver · Red Gold

IW5901-08 · 46 mm

IWC

Blue · Platinum

IW5901-09 · 46 mm

+ 1 more variant in this family.

IWC manufactured 94800 calibre (94000-calibre family) is a hand-wound movement with a tourbillon escapement. A patented constant force mechanism is integrated into the tourbillon, ensuring a stable amplitude of the balance - visible through 1 second jumps of the tourbillon. After having run for 48 hours, the constant force mechanism is decoupled and the tourbillon will move in regular 1/5th of a second intervals. It furthermore features a day/night indication, double moonphase display and a 96 hour power reserve.

13 other watches in the library run the IWC 94800.

IWC

Portugieser Constant-Force Tourbillon Double Moon Red Gold / Black

IW5901-07 · 46 mm

IWC

Portugieser Constant-Force Tourbillon Double Moon Red Gold / Ardoise

IW5901-01 · 46 mm

IWC

Portugieser Constant-Force Tourbillon Double Moon Red Gold / Blue

IW5901-06 · 46 mm

IWC

Portugieser Constant-Force Tourbillon Double Moon Platinum / Black

IW5901-04 · 46 mm