Short answer
A replica IW371633 is a copy of the IWC Portugieser Chronograph, a 41.1 mm steel watch with two sub-dials, a date at 3 o'clock and the in-house calibre 69355. Replica versions sell for about $180 to $700. The parts that separate a good copy from a poor one are case thickness, the spacing of the sub-dials at 12 and 6, the date font and the chronograph movement inside.
The genuine watch
IWC ref. IW371633 sits in the IW3716 family, the Portugieser Chronograph line that IWC refreshed in 2020. The case measures 41.1 mm across and 13.1 mm thick. Lug width is 20 mm. Water resistance is 30 m. The crystal is sapphire with an antireflective coating on both faces, and the back is sapphire with a view of the movement.
- Calibre 69355, automatic, made in house by IWC
- Column wheel chronograph with a vertical clutch
- 46 hour power reserve, 28,800 vph
- Small seconds at 6 o'clock, elapsed minutes at 12 o'clock
- Date aperture at 3 o'clock
- Applied numerals and leaf hands
IWC assigns a separate reference number to each dial and strap combination in this family. Before you buy, ask the seller to confirm the dial color, the strap type and the caseback engraving for the -33 number. If the seller cannot name those details, treat the listing as unclear.
What replicas get right
Top-tier copies reproduce the case profile, the stepped bezel and the thin bezel ring well. The printed minute track and the applied numerals look close at arm's length. The polished case flanks and the brushed caseback rim match the original finish pattern on the better versions.
What replicas get wrong
- Thickness. Many copies measure 13.8 mm to 14.5 mm because the movement is taller than the 69355. Ask for a caliper photo.
- Sub-dial spacing. On the genuine watch the two sub-dials sit close to the center line. Copies that use a stock chronograph layout push them apart.
- Date font. The numeral shape and the window bevel are common tells. Compare a close-up photo with an IWC catalog image.
- Hands. Genuine leaf hands are faceted and catch light along a center ridge. Flat stamped hands look dull.
- Rotor noise and winding feel. A rough crown and a loud rotor point to a low-grade movement.
Movements in replicas
Most copies use one of three movements. The Asian 7750 is common, runs at 28,800 vph and gives a 12 hour chronograph. A decorated 7750 marked as a clone 69355 is the same base with cosmetic plates. A few sellers offer a Seagull ST19 based option, which is a hand-wound column wheel design and does not match the automatic original. Ask which movement is fitted, and ask for a photo of the movement through the caseback. The 69355 has a distinct bridge shape and a black column wheel that a stock 7750 does not.
Checks before payment
- Request photos of the caseback, the crown side and the clasp.
- Ask for the measured thickness and weight in grams.
- Confirm the chronograph starts, stops and resets to zero.
- Confirm the date changes with the crown in the second position.
- Ask about the return window and the service interval.
Price bands
Low-grade copies sell for $180 to $250 and show thin plating and a stamped clasp. Mid-tier copies run $280 to $450 with a 7750 movement and sapphire on both sides. The top band, roughly $500 to $700, adds a closer case profile, better hand finishing and a bracelet or strap with correct stitching. A genuine IW371633 lists at about $8,000, so no replica price should approach that figure.
Legal note
Replica watches infringe trademarks and cannot be serviced by IWC. Customs in the US and the EU can seize shipments. Treat the purchase as a purchase of a copy, not of an IWC product.