Short answer

IW3270 is the reference group for the IWC Pilot's Watch Mark XVIII. IWC launched the Mark XVIII in 2016 as the successor to the Mark XVII. The steel case measures 40 mm across and 11 mm thick. The movement is Calibre 35111, an automatic with a 42-hour power reserve. Copies appear on the market because the dial is simple and the case is easy to machine. Photos hide most defects. Hands-on checks of the caseback, the crown, and the movement separate a copy from a genuine watch.

What the reference covers

IWC builds the Mark XVIII with several suffixes. IW327001 is the base version: stainless steel, black dial, calfskin strap. IW327002 adds a steel bracelet. Higher suffixes cover blue dials, titanium, and limited editions. IWC changes the catalog each year, so a suffix list from 2018 does not match a list from 2023.

Shared specs across the steel versions:

  • Case: stainless steel, 40 mm diameter, 11 mm thickness, 20 mm lug width
  • Crystal: sapphire with anti-reflective coating
  • Water resistance: 6 bar (60 m)
  • Movement: Calibre 35111, automatic, 25 jewels, 28,800 vph (4 Hz), 42-hour power reserve
  • Dial: black, white Arabic numerals, date at 3 o'clock
  • Lume: Super-LumiNova on hands and numerals
  • Strap: calfskin leather with a signed pin buckle

Calibre 35111 shares its base with the Sellita SW300-1. IWC adjusts the movement in house and fits its own rotor.

Points where copies fail

  • Caseback. The Mark XVIII caseback carries an engraved aircraft motif plus the reference and serial numbers. Copy engraving sits shallow, and the fonts drift.
  • Date window. Genuine date fonts are thin and centered. Copies show thick numerals and off-center placement.
  • Crown. The genuine crown is screw-down and signed. Threads engage in under two turns. Copies feel gritty and stop short.
  • Movement. A copy often runs a Miyota 9015 or a generic clone. A watchmaker can read the rotor, the jewel count, and the finish under a loupe.
  • Lume. Genuine Super-LumiNova glows even and bright for hours. Copy lume fades in minutes and looks patchy.
  • Weight and finish. The case mixes brushed and polished surfaces with sharp edges. Copies round the edges and weigh 5 to 15 grams more or less.

Checks that need a bench

Photo checks stop at the dial. Verification of a Mark XVIII needs a watchmaker. Steps:

  1. Open the caseback and identify the movement and rotor markings.
  2. Compare the serial against the reference on the caseback and the papers.
  3. Measure the case with calipers. A 40 mm case should read 40.0 mm, not 41 mm.
  4. Time the rate on a timegrapher. A healthy 35111 shows a consistent rate across positions.

A public serial lookup for this reference is not available. IWC service centers handle verification.

Legal and market notes

In the United States, trafficking in counterfeit goods is a federal crime under 18 U.S.C. § 2320. Customs and Border Protection can seize counterfeit watches at import and destroy them. Resale is illegal even when the buyer knows the watch is fake.

Genuine pre-owned Mark XVIII watches trade in the low four figures in USD. Condition, box, papers, and service history drive the spread. A price far under that band points to a copy or to a genuine watch with a swapped movement.