Short answer
A replica IW329170 is a copy of the IWC Aquatimer Automatic, a 42 mm dive watch. Copies sell for $150 to $500. The price tracks three parts: the movement, the crystal, and the bezel. A $150 copy runs a 21,600 vph Chinese movement behind mineral glass. A $400 copy runs a 28,800 vph movement behind sapphire and clicks through 60 bezel positions with no back-play.
The last two digits of an IWC reference mark dial and strap codes. Confirm the variant from caseback photos before you pay. If a listing shows a case size other than 42 mm, treat the reference number as wrong.
What the genuine watch is
The Aquatimer is IWC's dive line. The 42 mm reference carries a steel case, a rotating bezel, a screw-down crown, and a sapphire crystal. IWC lists 300 m (30 bar) of water resistance on Aquatimer Automatic 42 mm variants. The dial uses applied markers with Super-LumiNova fill.
Buyers pick this case size because 42 mm fits wrists from 6.5 to 7.5 inches. Copies aim at the same footprint.
Price tiers
- $120 to $180: mineral crystal, DG2813 movement, stamped clasp, painted markers.
- $200 to $320: sapphire crystal, Miyota 9015 or Seagull ST2130, solid end links, screw-down crown with tight threads.
- $350 to $500: Swiss ETA 2824 or a top clone, anti-reflective coating inside the crystal, better lume, deeper caseback engraving.
Checks before you pay
- Movement rate. Ask for a timegrapher photo. Target range: -10 to +10 seconds per day, amplitude 250 to 310 degrees, beat error under 0.5 ms.
- Date alignment. The date sits centered in the window on a correct date wheel.
- Bezel. 60 clicks, no back-play, triangle lined up at 12.
- Crown. Threads catch in under one turn. No wobble when pushed in.
- Crystal. Sapphire has a Mohs hardness of 9. A steel file marks mineral glass and leaves sapphire alone.
- Lume. Charge the dial under a phone light for 30 seconds. Check in a dark room.
- Caseback. Look at engraving depth and font. Shallow laser etching is the common flaw.
- Bracelet. End links sit flush with the case. No rattle when you shake the watch.
Movement options
Miyota 9015: 28,800 vph, 42 hour power reserve. A watchmaker can source parts.
Seagull ST2130: ETA 2824 layout, 28,800 vph. Swiss parts fit the same bridges.
DG2813: 21,600 vph. The seconds hand stutters. Parts do not interchange with ETA.
ETA 2824-2: 28,800 vph, about 38 hours of reserve. A service runs $100 to $200 at an independent shop.
Water resistance
The genuine watch is rated to 300 m. A replica has no rating you can trust. Gaskets, case tube fit, and caseback torque change from batch to batch. ISO 22810 sets the classification standard, and a copy ships with no test certificate. Two options: keep it dry, or pay a watchmaker $30 to $60 for a pressure test at 3 bar.
Legal note
Counterfeit goods carry a trademarked logo. U.S. Customs can seize shipments at import. Resale of counterfeit goods is a separate offense. Check the rules in your country before you order.