Portofino Chronograph 150 Years Stainless Steel / White

In Context

At 42 mm it is sized to the current mainstream: 40 mm is the median across every watch measured in this catalogue. At 13.5 mm it is a tall case, and it will catch on a cuff. The case back is closed, so the movement stays out of sight, 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 winds itself from the motion of your wrist. 44 hours of reserve carries it overnight, but not through a weekend in a drawer. At 28,800 vph the seconds hand advances 8 times a second.

IW3910-24 is one of 22 executions of the IW3910 base reference. Underneath they are the same watch; what separates this one is a white gloss dial and a stainless steel case. It was a limited edition. Introduced in 2018. Beyond the time it carries a chronograph.

IWC

Silver · Stainless Steel

IW3910-01 · 42 mm

IWC

Black · Stainless Steel

IW3910-02 · 42 mm

IWC

Silver · Stainless Steel

IW3910-05 · 42 mm

IWC

Black · Stainless Steel

IW3910-06 · 42 mm

IWC

Silver · Stainless Steel

IW3910-07 · 42 mm

IWC

Black · Stainless Steel

IW3910-08 · 42 mm

IWC

Blue · Stainless Steel

IW3910-19 · 42 mm

IWC

Blue · Stainless Steel

IW3910-23 · 42 mm

+ 13 more variants in this family.

The 79320 is IWC's Valjoux 7750, the day-date chronograph of the Pilot's Chronograph from 2006 until the in-house 69380 replaced it in 2019. It powers 49 watches in this library. IWC takes the 7750 base and rebuilds it to its own standard, which the [7750 piece](/blog/the-valjoux-7750-family) describes: the cam-actuated chronograph, the 6-9-12 counter layout and the day and date at 3 o'clock are the base's, and the finishing, regulation and a 44-hour reserve at 28,800 vph with 31 jewels are IWC's. At 30 mm across and 7.9 mm high it is a thick movement, and the 43 mm and 42 mm cases around it reflect that. In the library it sits under 30 [Pilot's Watch](/brands/iwc/pilot) references, the Chronograph ref 3777 of 2016 at 43 mm and the ref 3717 of 2006 at 42 mm, including the Le Petit Prince and Spitfire editions, 14 GST Aquatimer chronographs and 5 [Portofino](/brands/iwc/portofino) Chronographs. The 43 mm case accounts for 19 references and the 42 mm for 17. 18 are limited editions. The [79230](/calibers/iwc-79230) is the split-seconds version of the same base, the [79350](/calibers/iwc-79350) the Portugieser's variant without the day and date, and the [69375](/calibers/iwc-69375) the in-house family that succeeded it.

48 other watches in the library run the IWC 79320.

IWC

Aquatimer Chronograph Stainless Steel / Black / Bracelet

IW3768-04 · 44 mm

IWC

Pilot's Watch Spitfire Chronograph Stainless Steel / Silver / Strap

IW3717-02 · 42 mm

IWC

Pilot's Watch Spitfire Chronograph Stainless Steel / Silver / Bracelet

3717 · 42 mm

IWC

Pilot's Watch Chronograph Stainless Steel / Black / Strap

IW3717-01 · 42 mm