Zenith Chronomaster Sport 41mm Mens Watch Skeleton - Interchangeable Strap

Ref. 03.3131.3600/01.M3130

The El Primero has a particular claim to the chronograph story: it was one of the first automatic chronograph movements, and it has run at 36,000 vph since 1969 when almost everything else ran slower. The 3600 SK is that same high-frequency column-wheel movement opened up, its 311 components visible through a smoked sapphire base that shifts from near-black at the edges to something closer to charcoal at the centre. The three sub-dials are held in monochromatic grey rather than contrasted out, which keeps the skeletonised architecture readable rather than busy. At 5 Hz the central chronograph hand completes a full sweep every ten seconds, and the green ceramic bezel is graduated to match — so what you are actually timing is resolved to a tenth of a second by eye, without any electronic assistance. The bezel colour reappears in the rubber strap included alongside the bracelet, which is a considered touch: the steel bracelet carries a micro-adjustable folding clasp for daily wear, and the rubber offers a straightforward swap for anything more physical. At 13.6mm the case is not thin, but for a movement with this much happening inside it, that is not an unreasonable trade.

Reference

03.3131.3600/01.M3130

Brand

Zenith

Case size

41mm

Case thickness

13.6mm

Case material

Stainless steel

Case shape

Round

Dial

Black

Crystal

Sapphire

Movement

Automatic

Calibre

El Primero 3600 SK

Functions

Chronograph, Small seconds, Skeleton dial

Water resistance

100m

Bracelet / strap

Stainless steel bracelet

Strap colour

Green

Clasp

Folding clasp

Lume

Super-LumiNova

Retailer

Goldsmiths