IWC
IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901
The IWC Portugieser Hand-Wound Tourbillon Day & Night (reference IW545901) is a 42.4 mm 18k Armor Gold watch with a black dial. It runs on the manual caliber 81925 with a 84-hour power reserve and is water resistant to 60 m.
Specifications
Case
- Reference
- IW545901
- Collection
- Portugieser
- Case size
- 42.4 mm
- Thickness
- 10.8 mm
- Case material
- 18k Armor Gold
- Case shape
- Round
- Crystal
- Sapphire
- Water resistance
- 60 m
- Bracelet / strap
- Leather strap
Dial and bezel
- Dial
- Black
Movement
- Movement
- Manual
- Caliber
- 81925
- Power reserve
- 84 hours
- Frequency
- 28,800 vph
- Jewels
- 22
- Functions
- Flying tourbillon, Day & night indication
Production
- Production
- Current
Dial versions
This reference was made with these dials and finishes.
IW545901 Black
Black
How it compares within the Portugieser family
Side by side with other references in the same collection, from the catalog.
| Reference | Size | Material | Dial | Caliber | Years |
|---|---|---|---|---|---|
| IW545901 (This watch) | 42.4 mm | 18k Armor Gold | Black | 81925 | — |
| IW358304 | 40.4 mm | Stainless steel | Silver (blue hands) | 82200 | 2020– |
| IW358305 | 40.4 mm | Stainless steel | Blue | 82200 | 2020– |
| IW358310 | 40.4 mm | Stainless steel | Green | 82200 | 2020– |
| IW371604 | 41 mm | Stainless steel | Silver (gold-plated hands) | 69355 | 2020– |
| IW371606 | 41 mm | Stainless steel | Blue | 69355 | 2020– |
| IW371615 | 41 mm | Stainless steel | Green | 69355 | 2020– |
| IW371617 | 41 mm | Stainless steel | Silver (blue hands) | 69355 | 2020– |
| IW503703 | 44.4 mm | 18k white gold | Ice blue | 52616 | 2024– |
About the Portugieser family
The Portugieser began in the late 1930s, when two Portuguese merchants asked IWC for a wristwatch as precise as a marine chronometer. IWC fitted a pocket-watch movement into a large wristwatch case, which gave the line its size and its clean, railway-track dial.
The modern family includes the Portugieser Chronograph, first introduced in the 1990s and updated in 2020, the Portugieser Automatic with a seven-day power reserve, perpetual calendars, minute repeaters and tourbillons. Calibers in the catalog include the 52010 and 51011. Dealers identify the generation and metal from the reference and check the dial, strap and papers.
Quick answers
- What size is the IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901?
- The IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901 has a 42.4 mm case, 10.8 mm thick.
- What movement does the IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901 use?
- It uses the manual caliber 81925, with a 84-hour power reserve.
- How water resistant is the IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901?
- It is water resistant to 60 metres.
- Is the IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901 still in production?
- Yes, it is a current reference.
- What is the IWC Portugieser Hand-Wound Tourbillon Day & Night IW545901 made of?
- The case is 18k Armor Gold. Bracelet or strap: Leather strap.
Catalog facts checked October 2026.