Short answer
IW371758 belongs to the IWC 3717 reference block. That block covers the Pilot's Watch Chronograph sold from 2006 to 2012. The watch has a 42 mm steel case, a day and date window at 3 o'clock, and two subdials at 12 and 6. IWC does not make a replica. Any IW371758 sold as a copy comes from a third party factory, and the quality depends on the movement and the dial print.
What the reference covers
IWC groups references in blocks. IW3717xx covers the Pilot's Chronograph. IW371701, one suffix in the same block, is a black dial on a leather strap. Other suffixes change dial color, strap, or market. IWC has no current product page for IW371758, so confirm the dial color, hands, and strap in seller photos before you pay.
Specs to compare against the original
- Case: 42 mm steel, about 15 mm thick, brushed sides, polished bezel.
- Crystal: sapphire. Copies use mineral glass at the low end.
- Water resistance: the original is rated 6 bar (60 m). A copy seal is not tested. Keep it out of water.
- Movement: caliber 79320, 25 jewels, 28,800 vph, about 44 hours of reserve, day and date at 3.
- Lug fit: ask the seller for the lug width. Do not assume it matches the original.
Movement inside a replica
Three movement types show up in copies of this case. Quartz. The Asian 7750, also sold as the A7750. And a claimed Swiss ETA 7750. The A7750 is the common automatic choice. To put small seconds at 6 and the chronograph counter at 12, the factory has to modify the 7750 gear train. That adds parts and adds failure points. Ask which movement is fitted, then ask for a photo of the caseback and the rotor.
Five checks before you buy
- Day and date. The original shows both in one window at 3. Cheap copies print the day on the same disc as the date or leave a gap at the window edge.
- Subdial hands. The hand at 6 is small seconds and should sweep. The hand at 12 should sit at zero until the chronograph starts. If the hand at 6 is the 12 hour counter, the movement is an unmodified 7750 and the layout is wrong.
- Dial print. Check the IWC logo, the Schaffhausen line, and the minute track. Thick print and soft edges show up on low grade copies.
- Caseback. Engraving on copies is shallow. Compare the reference number, the serial style, and the tool notches.
- Pushers and crown. Pushers should start, stop, and reset with a firm click. The crown should screw down and set the day and date.
Price tiers
Copies of this case sit in three bands in the US market. Quartz versions run about $80 to $150. A7750 versions run about $250 to $400. Higher grade builds with a better dial and a serviced movement run $500 and up. A price well below the band for that movement type is a warning sign.
What a listing will not tell you
No seller names the true factory. Ask for the movement type, the case measurements, and a photo of the dial in daylight. Ask about the return window. If the answers are vague, move on.