The Portugieser Tourbillon Rétrograde Chronograph (Ref. IW394009) combines subtle problems with a daring aesthetic. Introduced in a 43.5 mm 18 ct Armor Gold® case with a thickness of 15.9 mm and three bar water resistance, it encompasses a black dial with sunburst end, gold-plated feuille arms, and appliqué markers.

At 6 o’clock, a flying minute tourbillon comprising 56 parts (weighing solely 0.635 g) is suspended beneath a domed sapphire crystal with anti-reflective coating on either side. Powering the watch is IWC’s in-house calibre 89900, providing a 68‑hour energy reserve at 28,800 vph. It integrates a chronograph with flyback perform and a retrograde date show arching between 8 and 10 o’clock. The sapphire caseback reveals wonderful ending and a stable gold rotor engraved with the Probus Scafusia seal. Precision engineering and refined design, assembled by hand with meticulous consideration to element.