Zenith Defy Skyline Chronograph 42mm Mens Watch Black Interchangeable Strap

Ref. 03.9500.3600/21.I001

The El Primero has been Zenith's defining movement since 1969, when it became the first automatic chronograph calibre to run at 36,000 vibrations per hour. The 3600 variant pushes that idea further: at 5 Hz the central chronograph hand completes a full sweep every ten seconds, making the 1/10th-of-a-second scale on the inner flange genuinely readable rather than decorative. That precision sits inside an octagonal case with a twelve-sided faceted bezel — an architectural form the Defy line has used to signal that it belongs to the sports end of what Zenith makes. The black sunray dial is engraved with Zenith's four-pointed star across its full surface, which means the pattern shifts as the light moves rather than sitting flat. The three sub-dials follow the classic El Primero layout, and the rhodium-plated hands carry C1 lume, so the watch reads well after dark without depending on it. The exhibition caseback is worth knowing about: it exposes the movement fully, and at 12.7mm the case is slim enough that this does not read as a watch built around its own bulk. The quick-change mechanism means the included rubber strap swaps in without tools, which is a practical detail on a watch rated for the water.

Reference

03.9500.3600/21.I001

Brand

Zenith

Case size

42mm

Case thickness

12.7mm

Case material

Stainless steel

Case shape

Octagonal

Dial

Black

Crystal

Sapphire

Movement

Automatic

Calibre

El Primero 3600

Functions

Chronograph, Date, Small seconds

Water resistance

100m

Bracelet / strap

Stainless steel bracelet

Strap colour

Silver

Clasp

Folding clasp

Lume

Super-LumiNova

Retailer

Goldsmiths