Portofino

IWC Portofino IW391031

Portofino Chronograph

  • 42mm
  • Steel
  • Automatic
  • Men's
The IWC Portofino, reference IW391031. Below are the full specifications, plus what each part of the reference number means. If you own this reference and want to know what it is worth today, we buy it outright and appraisals are complimentary.

Rather talk to someone? Call (619) 236-9603 Mon to Sat, or walk in at 907 Sixth Ave

GIA-trained appraisers · 20 years in downtown San Diego · 100% certified authentic

Full specifications

Case

Case size42mm
Case materialSteel
CrystalSapphire, convex, antireflective coating on both sides
Water resistance30m

Bezel

Bezel typeSmooth
Bezel materialStainless steel

Dial

Dial colorBlue
LumeSuper-LumiNova

Movement

MovementAutomatic, Caliber 79320
Caliber79320
Power reserve44 hours
Beat rate28800 vph
Jewels25
FunctionsHours, minutes, small seconds, day, date, chronograph

Reference

Wears asMen's

How the IW391031 compares

Side by side with the other IWC Portofino references we document. Only the specs that actually differ are listed.

IW391031 vs IW356501

SpecIW391031 IW356501
Case size 42mm 40mm
Dial Blue Silver
Power reserve 44 hrs 42 hrs

IW391031 vs IW356502

SpecIW391031 IW356502
Case size 42mm 40mm
Dial Blue Black
Power reserve 44 hrs 42 hrs

IW391031 vs IW356523

SpecIW391031 IW356523
Case size 42mm 40mm
Power reserve 44 hrs 42 hrs

Common questions about the IWC Portofino IW391031

How big is the IWC Portofino IW391031?

The case measures 42mm across. Case material: Steel. Case size alone is a poor guide to how a watch wears; lug-to-lug length and how the bracelet drops off the case matter more, which is why we suggest trying one on before you commit.

What movement is in the IW391031?

Automatic, Caliber 79320. Power reserve is 44 hours. It beats at 28,800 vph. The movement uses 25 jewels.

Is the IW391031 water resistant?

It is rated to 30 meters, about 98 feet. That covers rain and hand washing. It is not rated for swimming. One caution that applies to every watch on this page: a water resistance figure describes a new watch with fresh gaskets. On a piece that is years past its last service, treat the rating as unknown until it has been pressure tested.

Does the IW391031 have a nickname?

Portofino Chronograph. Collector nicknames are not official IWC names, but they are what people actually search for and what they are called across a showroom.

Does San Diego Jewelry Buyers buy the IWC Portofino IW391031?

Yes. We buy this reference outright, and we lend against it if you would rather keep it. We are a family-owned San Diego buyer established in 2006, our appraisers are GIA-trained, and the appraisal is complimentary with no obligation to sell. You can bring it to our Gaslamp showroom at 907 Sixth Ave or start online. If you are looking to buy this reference instead, tell us and we will let you know when one comes in.

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  • GIA-trained watch buyer
  • BBB A+ accredited
  • Family-owned in San Diego since 2006
  • Paid on the spot, in person

Interested in a Portofino IW391031?

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Own a Portofino IW391031?

We buy this reference outright, and we lend against it. Bring it to our Gaslamp showroom or start online. Appraisals are complimentary and there is no obligation to sell.

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