Short answer
IW329108 is one reference number in the IWC Aquatimer family. The letters IW and the first four digits name the case and model group. The last two digits name the variant: dial color, hands, strap or bracelet, and sometimes case metal. Two watches can share a case and differ only in those last two digits.
We could not find a public lookup table that maps every IWC suffix to a dial color. Confirm the dial, strap and metal on the IWC product page or on a dealer listing for that exact number before you buy a first copy.
How to read the number
- IW: the prefix IWC puts on every reference.
- 3291: the case and model group. Aquatimer Automatic, 42 mm case.
- 08: the variant code inside that group.
This is why IW329108 and IW329101 can look like the same watch in a small photo. The case, crystal and bezel are the same. The dial and the strap are not.
What changes between variants
- Dial color and finish. Black, blue and silver dials appear across the Aquatimer Automatic range.
- Indexes and hands. Some dials use lume-filled markers, others use applied metal.
- Strap or bracelet. Rubber with a pin buckle, rubber with a folding clasp, or a steel bracelet.
- Case metal. Steel and titanium both appear in the line.
- Bezel insert. Steel, black or blue.
Ask the seller for a photo of the caseback engraving. A first copy that carries the wrong suffix is a mismatched watch, not a variant.
Case and bezel
The Aquatimer Automatic 42 runs a 42 mm case, an internal rotating dive bezel, and a crown at 4 o'clock. On the genuine watch the outer bezel drives the inner ring. Turn the outer bezel and watch the inner scale. It should move with it and click at each mark. On low-grade copies the inner ring is fixed or printed on the crystal.
Movement
IWC fits a 30-series automatic caliber to the Aquatimer Automatic. Third-party listings name caliber 30120. If the paperwork does not name the caliber, treat the claim as unverified.
First copy IW329108 watches use one of three movements: a Seagull ST21, an ETA 2824 clone, or a Miyota 9015. The Miyota beats at 28,800 vph and hacks. Ask which movement is inside. A photo of the movement, with the caseback off, is the only proof that counts.
Water resistance
Genuine Aquatimer watches carry a dive rating from the factory. First copies carry a claim. A 300 m claim on a case with a press-fit back and no pressure test is a number on paper. Do not dive with a first copy. Do not swim with one until a watchmaker has tested it.
Tells to check on a first copy
- Bezel action. The inner ring must rotate with the outer bezel.
- Date window. Check alignment and magnification.
- Lume. Charge it under a lamp for 30 seconds, then compare the glow to a photo of the genuine dial.
- Engraving depth on the caseback.
- Screw heads on the caseback and lugs. Look for burrs and off-center slots.
- Strap feel. Rubber copies are stiffer and smell of new tire.
Price bands
First copy Aquatimer watches sell from about $150 to $500. Copies with a Miyota 9015 or a decorated ETA clone sit at the top of that band. Anything above $700 for a steel dive watch copy needs a movement photo and a named factory before money changes hands.
Before you pay
- Ask for the exact reference the seller is shipping.
- Ask for dial, caseback and movement photos of that unit.
- Confirm case diameter, lug width and strap type in writing.
- Confirm the return window in days, not words.