Short answer
A replica IW329147 copies the IWC Aquatimer Automatic 42. The case measures 42 mm across and about 14 mm thick. The dial has a date at 3 o'clock and a dive scale under the crystal. Price runs from $120 for a quartz or low-grade automatic build to $400 and up for one with a Miyota 9015 or Sellita SW200-1 inside. No replica of this watch passes ISO 6425 dive testing. Do not dive with one.
The reference behind the number
IWC groups its Aquatimer Automatic 42 models in the IW3291 block. The last three digits mark a dial, strap, or case finish. IWC lists the family at 42 mm, 300 m water resistance, sapphire crystal, and calibre 30120. That calibre beats at 4 Hz and holds about 42 hours of power. Public listings for the exact 147 suffix are thin, so compare a photo of the caseback against the dial and strap in the listing. If a seller shows only one of the two, treat the reference number as unverified.
What separates a good replica from a bad one
- Case: 42 mm wide, 14 mm thick. Cases at 12 mm are the wrong shape.
- Crystal: flat sapphire with inner anti-reflective coating. Mineral glass scratches and turns blue at the edge.
- Bezel: the inner dive scale must turn. It should sit on the 12 o'clock index and hold position when the watch is shaken.
- Dial: printed lume plots, not stickers. Date font must match the original.
- Lume: holds a glow for 4 hours or more. Weak lume fades in 20 minutes.
- Strap: 22 mm lugs, rubber or steel. Quick-release spring bars are a plus.
Movements
Three movements appear in this replica. A 21,600 vph Chinese automatic with 21 jewels is the base option and holds about 36 hours of power. The Miyota 9015 runs at 28,800 vph, 24 jewels, 42 hours of reserve, and hacks. The Sellita SW200-1 runs at 28,800 vph, 26 jewels, and about 38 hours of reserve. The 28,800 vph movements give 8 beats per second and a smoother sweep. Ask for a movement photo through the caseback before payment.
What no replica gets right
Bezel feel, water resistance, and movement finish. Replica gaskets are untested. A pressure test at a watch shop costs $20 to $40, and most sellers will not cover a failure. Caseback engraving depth is shallow. The movement is not adjusted in 5 positions. Crown threading feels loose after a few months of use.
Checks before you pay
- Ask for a photo of the movement through the caseback.
- Ask for a video of the second hand and the date change.
- Ask for caliper photos of case diameter and thickness.
- Confirm the return window in days and who pays return shipping.