Zenith puts the El Primero in two very different watches, and buyers regularly ask us which one to get. The honest answer is that they are not really competing for the same wrist.
The Short Answer
The Chronomaster Sport is a 41mm chronograph running the El Primero 3600, built to chase the Rolex Daytona at roughly a third of the price. The Defy Skyline is a 41mm integrated-bracelet sports watch running the El Primero 3620, built to compete with watches like the Royal Oak and Nautilus. One is a chronograph first. The other is an integrated bracelet sports watch that happens to show off a high-frequency movement through an openworked dial.
The Defy Skyline. The octagonal faceted bezel and integrated bracelet put it in Royal Oak and Nautilus territory, not Daytona territory.
What Each Watch Actually Is
The Chronomaster Sport: A Daytona-Style Chronograph
The Chronomaster Sport runs the El Primero 3600, a 5Hz automatic chronograph that measures to a tenth of a second, with roughly 60 hours of power reserve and a retail price around $11,000. We cover the full case for this watch, including the direct Daytona comparison, in our Chronomaster Sport buying guide.
The Chronomaster Sport's black ceramic bezel and tri-color subdials are a direct answer to the Daytona.
The Defy Skyline: An Integrated Sports Watch
The Defy Skyline runs the El Primero 3620, a related but distinct 5Hz automatic that drops the chronograph pushers and instead displays a running 1/10th-of-a-second indicator directly on the dial. The steel model retails around $9,000, carries 60 hours of power reserve, and is rated to 100 meters, per aBlogtoWatch's Defy Skyline review.
Side by Side
| Spec | Chronomaster Sport | Defy Skyline |
|---|---|---|
| Case diameter | 41mm | 41mm |
| Movement | El Primero 3600 | El Primero 3620 |
| Function | Chronograph, 1/10th second | Running 1/10th-second indicator, no chronograph pushers |
| Power reserve | ~60 hours | ~60 hours |
| Water resistance | 100m | 100m |
| Bracelet | Steel with black ceramic bezel | Integrated steel bracelet, octagonal faceted bezel |
| Approx. retail | ~$11,000 | ~$9,000 |
Why the Movements Are Different Even Though Both Are El Primero
The 3600 is built around a traditional chronograph architecture: pushers, subdials, a bezel that echoes a Daytona. The 3620 strips out the chronograph function entirely and repurposes the El Primero's high-frequency 5Hz base to drive a live 1/10th-second display instead, since there is no stopwatch function to time with it.
How They Wear Differently
Both cases measure 41mm, but the experience on the wrist is not comparable. The Chronomaster Sport sits on a steel bracelet with a conventional round chronograph silhouette. The Defy Skyline is an integrated-bracelet design with an angular, faceted octagonal bezel that pulls the whole watch tight to the wrist, in the same design language as the brand's original 1960s Defy.
On the wrist, the Defy Skyline's integrated bracelet pulls tight to the case, reading as a modern sports watch rather than a traditional chronograph.
Who Actually Buys Each One
Buyers shopping the Chronomaster Sport are almost always chronograph shoppers first, usually cross-shopping it directly against a Daytona or a Speedmaster. Buyers shopping the Defy Skyline are integrated-bracelet sports watch shoppers, cross-shopping it against a Royal Oak or a Nautilus rather than anything with pushers.
The Honest Trade-Offs
The Chronomaster Sport's chronograph function is genuinely useful and the bezel comparison to the Daytona helps it in resale conversations, but it wears as a more traditional round case.
At 41mm the Chronomaster Sport wears as a modern round chronograph, not an integrated-bracelet sports watch.
The Defy Skyline's integrated bracelet and angular case are more distinctive on the wrist, but the watch gives up the actual chronograph function that the movement family is famous for. If timing a lap or an interval matters to you, the Skyline cannot do it. It only displays the tenth-second rate, it does not start or stop anything.
Which One Should You Buy
Buy the Chronomaster Sport if you want a working chronograph and you are already comparing it to a Daytona or Speedmaster. It is the more direct value play against the watches it is usually cross-shopped with.
Buy the Defy Skyline if you want an integrated-bracelet sports watch with real technical presence on the wrist and you were never going to use a chronograph pusher anyway. It competes on design and movement visibility, not on stopwatch function.
Related Reading
For the deeper case on the Chronomaster Sport against the Daytona specifically, see our Chronomaster Sport buying guide. For how column wheel and cam-lever chronograph architectures compare more broadly, including the El Primero's own switching system, see our chronograph movements explainer. And if a tachymeter or dive bezel is part of your decision either way, our watch bezel types guide breaks down what each bezel style actually does.
FAQ
What is the difference between the Zenith Chronomaster Sport and Defy Skyline?
The Chronomaster Sport is a traditional round chronograph running the El Primero 3600 with working pushers and subdials. The Defy Skyline is an integrated-bracelet sports watch running the related El Primero 3620, which displays a running 1/10th-second indicator instead of a working chronograph function.
Which Zenith is cheaper, the Chronomaster Sport or the Defy Skyline?
The steel Defy Skyline retails around $9,000, roughly $2,000 less than the Chronomaster Sport's approximately $11,000 retail price.
Does the Defy Skyline have a working chronograph?
No. The Defy Skyline's El Primero 3620 displays a running tenth-of-a-second indicator on the dial, but it has no chronograph pushers and cannot start, stop, or time an interval.
Is the Zenith Defy Skyline a Royal Oak alternative?
It is commonly cross-shopped against integrated-bracelet sports watches like the Royal Oak and Nautilus because of its angular case and bracelet design, though it sits at a lower price point than either.
Which Zenith holds its value better, the Chronomaster Sport or Defy Skyline?
Neither model matches Rolex or Audemars Piguet resale performance. Both are bought primarily for the movement and design rather than as a value play, with pre-owned examples of each typically trading below retail.
Browse authenticated pre-owned Zenith at 5dwatches.com.