Hands-On Zenith Chronomaster Sport (1/10th Second Chronograph)

The Skinny

  • Size: 41mm
  • Movement: Zenith 3600 1/10th second chronograph
  • Water resistance: 100m
  • Price: $10,000 bracelet / $9500 rubber band

First impressions

It’s a long time since the El Primero debuted as the world’s first automatic chronograph back in early 1969. There have been many intermediate Zenith models in that time, however this latest Chronomaster Sport model is comfortingly familiar. With the Sport, Zenith have re-used the classic  blue, anthracite and light grey overlapping subdials of that original 1969 a386 El Primero chronograph. Is there a more iconic chronograph dial? The Rolex Daytona and the Omega Speedmaster would argue against that I suppose but I don’t think so… and talking of the Daytona, the new El Primero bears more than a passing resemblance to it with that black ceramic bezel.

No Ordinary Chronograph

Attempt to time anything on this watch and it will become immediately apparent that this is no chronograph in the 1969 model’s image. In fact, it will take you exactly a 1/10th of a second to realize what that long red-tipped center sweep hand is now timing tenths of seconds rather than seconds. Instead of making one revolution per 60 seconds as a regular chronograph, the Sport’s hand rotates once every 10 seconds, in 1/10th of a second increments.

The Sport is not the first 1/10th chronograph, Tag Heuer, Longines and Zenith themselves have made them before. It’s not the most precise mechanical chronograph either, Zenith made a 1/100 chronograph in 2018 with the Defy 21. The Sport is not even the first El Primero to have this feature since the limited edition Zenith El Primero Striking 10th from 2010 had the same function and a very similar dial. However, that was 10 years ago, and the Striking 10th was a limited edition of only 1969 steel watches. The Chronomaster Sport is not a limited edition, is available now and has a brand new El Primero 3600 movement. As with all Zenith caliber’s, it is fully developed and manufactured in-house.

36000 is the Magic Number

Growing up my favourite number was always 4. I don’t know why, I just remember blurting out ‘4’ whenever anyone asked. I suspect I was 4 years old the first time someone asked and that was the limit of my thought process back then. Now as a watch enthusiast with an interest in hi-beat movements, my favourite number is obviously 36000. I feel like it is the perfect beat rate for a mechanical watch. I am wearing my Sieko Lord Matic 36000 as I write this and its 10 vibrations per second sweep hand is smooth enough to entrance me but has just enough visible mechanical vibration that it does not scare me into thinking time is racing away out of my control. 

The 3600 movement is all new from Zenith

36000 vibrations per hour are also necessary to obtain the mechanical resolution to measure 1/10th of a second. The escapement locking/unlocking 10 times per second, provides the precise mechanical impulses necessary to move the sweep hand on one 1/10 of a second increments. The drive for the center sweep is taken directly from the main escapement and transmitted to the center seconds hand via a small secondary gear train that on close inspection reveals a beguiling treat for the observer. With a multiple of 10 teeth on each gear of this train, the teeth appear paradoxically frozen in time while the curved spokes of the gears rotate around as expected. It is quite the movement’s party-trick.

The two wheels of the 1/10 second train (center) driven off the top of the escape wheel (right)

This is not a movement with hand finished polished bevels and machined bridges. The appearance is far more functional and high-tech, with bridges cutaway as if to reduce weight on a race car. The resultant CNC’d filigree appeals to my engineer’s eye just as much a haute horology movement does to my artist’s heart. Zenith’s caliber 3600 has that skeletonized-grey look of the Oris Pro-Pilot X and reminds me this is more like a Terminator movie than The Great Gatsby.

As with many modern movements, the power reserve is a step up from the movements of old and the 3600 comes in with a minimum of 60 hours. The winding weight is hefty even though much of the top surface is, like the bridges, machined away to provide a better view of the proceedings when viewed through the sapphire glass caseback. The mass is all at the edge where the rotor rotates in a deep trough surrounding the movement giving the impression of a smaller caliber in a larger case. Running at 36000 vph typically requires a stronger main spring with more torque so the requirement for a larger than usual winding weight is not surprising here.

A Very Well-Dressed Tool Watch

The case is similar to the existing Chronomaster El Primero Open and 386 Revival editions but at 41mm lies between the Open’s 42mm and the Revival’s 38mm. The near-perfect proportions are apparent immediately. The bezel is the right thickness, neither too vintage-narrow and not too modern-wide. The case is simple with polished sides and brushing on top. A polished bevel flows from one lug around the watch to the opposite lug in an elegant curve. The lugs are modern and minimal and connect the watch to the bracelet by tapering down simply. There are some nice crisp transitions between the polished bevel and the brushed top surface but we are not talking Grand Seiko levels of finished here. They are good but not amazing.

Chronomaster variants

On the wrist, the slightly smaller size is a welcome one for my 7.25″ wrist and I found it was that perfect “neither too large nor too small” size. The watch is well-balanced and although there is obviously some heft from the weight of an automatic chronograph movement, it seemed like that weight was held close to my wrist making it feel secure rather than precarious. I temporarily swapped to a leather band, since that is always my preference from a comfort perspective, and the watch felt just as good on that which was extremely comfortable.

The pitch black ceramic bezel framing the snow white dial dominates the look of the watch and adds significantly to its wrist presence. People will surely compare this this watch and its tri-compax looks with the Rolex Daytona and for me, the Zenith is the more dynamic design and better looking watch. I wear a lot of watches around my house and most go unnoticed by the family but not this one. It commanded both immediate notice and admiring comments on it’s good looks. It’s a totally subjective judgement of course, but I find this to be one of the best looking watches I have worn. The combination of the stark white dial, jet black bezel, and the complementary blue and grey subdials makes for a stunningly good-looking watch. The lack of metal edge on the bezel here helps too, keeping the look clean and contemporary and being ceramic, will ensure these well-balanced, well-proportioned good looks will stay looking like that for a long time.

Overall, the Chronomaster Sport is a high-quality watch coupled with a modern look evolved from a vintage classic. Its not glitzy, its not even a dressy tool watch… I’d call it simply a well-dressed tool watch. The crystal has a very slight curve to it that hints at the vintage heritage but everything else is bang up to date style-wise. Water resistance is a rain-proof 100m rather than a pool-friendly 200m on account of the crown and pushers not screwing down. For me this is the more practical choice over having more water resistance with the inconvenience of screw-down pushers. It also gives a cleaner, leaner look to the pushers. The upper start pusher was stiff on the review example so it seemed this watch was tuned for a hard start and soft reset. If it were my example I’d request a little more even balance between the two pushers during service.

Clarity Above All Else

The dial features both running seconds subdial (left hand, light grey) and chronograph seconds subdial (right hand, blue) accompanied by a 60-second accumulation subdial (center, dark grey) in between. The short running seconds hand, driven by the 36,000 vph movement, has no perceptible tick and is as smooth as any Spring Drive from Grand Seiko. Multiply that drive by the length of the center seconds hand and the movement vibrations become visible. The stark black and white bezel is divided into the 1/10ths of a second corresponding to the sweep hand’s progress. Reading the chronograph means reading both the center sweep against the bezel for 1/10s and the small chronograph seconds sub dial for elapsed seconds. Therefore, there is a little more work to do to read the timing compared to a regular chronograph. As a result, I would have preferred both the small seconds hand and the minute register hand to have been painted completely red rather than just the tip to aid its visibility, but this is a small niggle.

The rhodium-plated hour and minute hands are well finished with a center lume section terminated with black painted infilled sections. The center sweep hand is good quality with no rivet showing but it has just a hint of distortion in flatness where it attaches to the pinion.

The trapezoidagon markers are the modern variant we have seen before from Zenith on the Chronomaster Open and the El Primero Striking Tenth. There is a small section of lume on the trapezoidal end reminding me of the ‘cats eyes’ lane dividers common on European roads. A solid area of black paint on top of each marker is consistent with the general, high-contrast, high-legibility approach Zenith have taken. An applied Star logo completes a dial that prioritizes clarity above all else.

Dial and Bracelet Options

The Chronomaster Sport comes with two dial optionas and three bracelet options. My review sample had the white dial combined with the stainless steel bracelet but this version can also be ordered with a blue rubber strap. The black-dialed version is available on the stainless steel bracelet or black rubber strap. Both of the rubber straps have a Cordura texture molding on them and will save you $500 on the retail price compared to the bracelet version. My choice of spec would be the white dial with the stainless bracelet, as reviewed here.

The links of the steel bracelet have a solid, high-quality feel. Each is well finished, polished in the center and brushed at the edges. The edges themselves have small bevels which are further polished to stop anything feeling too sharp. The clasp is understated and functional but feels a little less refined than the rest of the watch. Finally, the machined end links have a fit and finish that is close to perfect.


The Zenith Chronomaster Sport is a compelling proposition. It provides a brand new, cutting edge, in-house chronograph movement with an uncommon, if not completely new, 1/10 timing function. It has a hi-beat caliber from a movement family has just about as much history as any chronograph movement can have. This latest ‘El Primero’ resides at the modern end of a lineage that includes both the very first automatic chronograph shown to the public, and movements that were Rolex’s choice for the Daytona before it had an in-house movement. The watch is then cased and dialed in a contemporary design with an abundance of wrist presence. It’s difficult, nay impossible, not to recommend this watch for anyone looking for an exceptional modern automatic chronograph from a storied manufacturer… and to be honest… I have already started saving for mine.