Answer first
IW371704 is a dial code in the IWC Portugieser Chronograph line. A copy IW371704 is a replica of that watch. The genuine piece has a round steel case near 41 mm, two chronograph subdials, a date at 3 o'clock, and a leather strap. Replica sellers price it from $180 to $450. The movement sets the price. IWC does not publish a full spec sheet for every dial code, so confirm case size and caliber against IWC or an authorized dealer before you buy.
Genuine specs
IWC groups several dial codes under one case. The list below covers the 3717 and 3716 families.
- Case: stainless steel, 40.9 mm on older builds, 41 mm on 2020 and later builds.
- Thickness: 12.3 mm to 13.1 mm, based on version.
- Dial: silver-plated, applied numerals, two subdials.
- Movement: caliber 79350 (Valjoux 7750 base) on older refs, caliber 69355 on newer refs.
- Water resistance: 3 bar, 30 m.
- Strap: 20 mm lug width, alligator on the genuine watch.
Replica grades
- Entry: $60 to $120. Quartz or a 21-jewel automatic. Mineral glass. Printed subdials.
- Mid: $180 to $280. Asian 7750 (A7750). Sapphire crystal. Steel case.
- High: $300 to $450. A7750 with a decorated rotor. Sharper dial print. Correct subdial spacing.
- "Swiss" claims: $600 and up. Some sellers swap in an ETA 7750. Others do not.
The A7750 has a date wheel position that differs from the IWC 79350. That difference moves the subdials and the date window. Check dial photos against a ruler.
Checks before you pay
- Ask for movement photos with the caseback open.
- Check subdial placement at 12 and 6.
- Time the chronograph. Pushers that grind on start are a bad sign.
- Measure the case across, without the crown. Replicas run 41.5 mm to 42.5 mm.
- Check the date font and the crown engraving.
US legal status
Customs and Border Protection seizes counterfeit watches at the border. 19 U.S.C. 1305 bars import of goods that carry a copied trademark. 18 U.S.C. 2320 sets a penalty of up to 10 years for trafficking. One copy for personal use carries civil risk more than criminal risk. Resale is a separate matter. A sale can bring a trademark suit under 15 U.S.C. 1114.
Open questions
IWC does not post an archive page for every dial code. The case size and caliber tied to IW371704 are not confirmed in this guide. Use IWC's site or a dealer to verify before you treat any seller spec list as final.