Quick answer
IW545105 is an IWC reference number in the Portuguese family. The base reference is IW5451, the Portuguese Hand-Wound. The last two digits, 05, mark one combination of case metal, dial color and strap. IWC does not publish a public suffix table. I cannot confirm which exact dial, metal and strap IW545105 is.
A replica IW545105 is a counterfeit copy of that watch. Sellers put the reference in listings to match search terms. Most listings use the number as a loose match. The watch shipped often does not match the reference it claims.
What the base reference is
The Portuguese Hand-Wound measures 44 mm across. It runs a hand-wound movement with small seconds at 6 o'clock and applied Arabic numerals. IWC lists power reserve in the 46-hour range for the 98295 caliber family. Case metal options include stainless steel, rose gold and white gold. Strap options include alligator leather in black, brown and blue.
The suffix is the variant code. IW545101 through IW545106 cover different metal, dial and strap builds. Buyers who search one suffix want one exact look.
Specs buyers compare
- Case diameter: 44 mm on the original. Copies run 41 mm to 45 mm.
- Lug width: 22 mm.
- Thickness: about 10 mm on the original.
- Crystal: domed sapphire with anti-reflective coating on both sides.
- Water resistance: 30 m as stated by IWC.
- Dial printing: "IWC" and "Schaffhausen" in two lines, thin serif type.
Movements used in copies
Hand-wound Portuguese copies use one of three movement bases:
- Seagull ST36 or ST3600, a Chinese build of the ETA 6497 layout.
- Asian 6497 and 6498 clones with added decoration plates and blued screws.
- Claimed Swiss ETA 6497-1. Most listings that say this ship an Asian movement. Ask for a movement photo before paying.
Declared jewel counts on copies run from 17 to 21. Bridge engraving is stamped, not cut. Perlage and Geneva stripes on copies are shallow and uneven under a 10x loupe.
Tells and mismatches
- Suffix mismatch: a seller advertises IW545105 but ships a dial and case from another suffix.
- Subdial height: the small seconds hand on the original sits close to the dial. Copies sit higher.
- Font weight: printed numerals on copies are heavier.
- Caseback text: reference number, case number and "Swiss Made" spacing. Copies smudge the gaps.
- Strap: original alligator is hand-stitched. Copies use embossed cowhide.
Legal and practical notes
Counterfeit watches are illegal to import, sell or traffic in the United States. 18 U.S.C. § 2320 covers trafficking in counterfeit goods. U.S. Customs and Border Protection seizes counterfeit shipments at ports and can destroy them. A buyer who imports one risks seizure with no refund.
Repair is the second problem. Parts do not interchange with genuine IWC service parts. Independent watchmakers often decline to service counterfeit movements. Water resistance claims on copies are untested and often false.
What is not known
IWC does not publish a suffix table. No source I checked confirms the dial, metal and strap of IW545105. A listing that states it with certainty is guessing. Treat the suffix as a search term, not a specification.