A fake IW329070 is a counterfeit copy of the IWC Aquatimer Automatic reference IW329070, a 42 mm steel dive watch with an internal rotating bezel and a genuine IWC automatic calibre inside. The fakes sell for $80 to $400. A real one trades well into four figures. That gap is the first signal, and it is the easiest one to check before you touch the watch.
No single detail proves a watch is fake. Counterfeiters get some details right and miss others. Work through the checks below in order and you will separate the two quickly.
The quick checks
- Compare the asking price against the going rate for the reference. Genuine IW329070 examples sit in the low four figures on the used market. An unboxed example at $250 is a replica, not a bargain.
- Measure the case with calipers. The genuine piece is 42 mm across the case, excluding the crown, and about 14 mm thick. Fakes commonly run a half millimeter to a full millimeter off in either direction.
- Tilt the crystal under a desk lamp. Genuine IWC crystals carry an anti-reflective coating on both faces and show a faint blue-violet cast. Replicas either have no coating or a heavy purple tint that flattens the dial.
- Rotate the outer bezel. On a genuine IWC Aquatimer the outer ring drives the inner dive scale through the SafeDive system. The action is firm, indexed, and moves the internal triangle in step. Fake bezels drag, wobble, or turn the inner ring out of alignment.
- Inspect the dial print under a loupe. Applied indices should sit flush with polished edges and even lume. Printed text should be crisp with correct letter spacing. Blurry edges, uneven lume, and crooked markers are the most common replica flaws.
- Check the date window. The date should sit centered in the aperture, with a font that matches the dial text. Replica date wheels often use a wider, flatter numeral set.
- Read the caseback engraving. Reference number, serial, and model text should be cut deep and sharp. Laser-etched or shallow stamping that catches light unevenly points to a copy.
- Have the watch opened by a watchmaker. The genuine movement is an IWC calibre with striped bridges, perlage, and an engraved rotor. Replica cases usually hold a generic Chinese automatic, a rebadged ETA clone, or a quartz module.
Where fakes fall short
- Case finishing. Genuine pieces show a clean line between brushed flanks and polished bevels. Fakes blur the transition or polish surfaces that should be brushed.
- Crown threads. The genuine crown screws down in a few smooth turns. Replica threads feel gritty or catch before seating.
- Weight and balance. A fake on a steel bracelet usually feels light and shifts on the wrist. Genuine bracelets have tight end-link fit and no rattle.
- Strap hardware. Buckle and clasp engraving on a fake is shallow and often uses the wrong typeface.
- Box and papers. Replica packaging is close but the printing on cards and manuals is soft, and the warranty documentation does not verify.
Buying used
Ask the seller for the reference and serial, then confirm the reference exists in IWC's own records. Request photos of the caseback, the crown, and the movement through the caseback if it has a display back. Meet at a watchmaker for a movement inspection on anything over a few hundred dollars. If the seller refuses an inspection, walk away.
Bottom line
The reference number on a fake IW329070 can be correct while everything under it is wrong. Price, bezel action, crystal coating, dial print, and movement finish carry the weight. Any one of them raises a question. Three of them together answer it.