Zenith Defy Extreme Diver Topper Edition is a watch that looks like it came from the bottom of the sea

Summary California jeweler Topper and Swiss watch giant Zenith have joined forces to create a watch that literally mimics the natural glow of the ocean. With only 50 pieces made and a price tag of over $12,000, it's a diver's watch that combines the high-frequency power of the El Primero with the aesthetics of the deep sea. It's the Zenith Defy Extreme Diver.

If you thought 2025 was already over with surprises in the world of watchmaking, you were wrong. Californian Trader Topper Jewelers has apparently decided that December is not the time to rest. After recently introducing a special edition watch DOXA, have now teamed up with Zenith to create something that even Aquaman could easily wear if he had deep enough pockets. So let's take a look – Zenith Defy Extreme Diver.

We're talking about the Zenith Defy Extreme Diver "Bioluminescence" Topper Limited Edition. And let's be honest, it's one of those watches that makes you stop and look twice.

Zenith's return to the depths

Zenith is a brand most people know for its chronographs and legendary El Primero movement, which measures tenths of a second. However, they have recently made an aggressive comeback into the world of diving lessons. Model Defy Extreme Diver, originally presented at the Watches & Wonders 2024 trade show, is a modern interpretation of their 1969 model.

Back then, it was a robust “machine,” shockproof and water-resistant to a depth of 600 meters. Today, the story is similar, except that materials technology is light years ahead. Zenith isn’t just trying to copy the past; they’re trying to build on it in a way that’s both technically impressive and visually appealing.

When the lights go out, magic happens.

The star of this watch is not the case, but the dial. Most diving watches are used to the standard application of luminous material on the hands and indices. Topper and Zenith have gone a step further.

They drew inspiration from bioluminescence – that natural phenomenon where plankton and sea creatures emit light in the dark. They applied tiny dots of Super-LumiNova coating to the dial, scattered like stardust or, in this case, luminous plankton. The result? When you turn off the light, the watch looks less like a timepiece and more like a piece of the ocean on your wrist. It’s the kind of detail that separates a collector’s piece from an ordinary watch.

Technical performance without compromise

Let's leave aesthetics aside and look at the specifications, because we are tech enthusiasts after all.

Housing: It is made of titanium, which means that the watch is extremely light despite its 42.5 mm diameter.
Waterproof: 600 meters (60 ATM). The watch has a helium escape valve, which is essential for saturation diving, although we know that most of these watches will only see water in the home pool.
Mechanism: Inside beats the heart of the El Primero 3620. This is a high-frequency movement that operates at 36,000 vibrations per hour (5 Hz).

One of the best decisions on this model? They removed the date. It's a move that purists love. Without a date window, the dial is symmetrical, clean, and allows the wave texture and luminous effect to really take hold.

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Ribbons and accessories

Zenith has included its quick-change strap system, which is one of the best on the market. No tools are required and there is no risk of scratching the case. The watch comes with an integrated titanium bracelet, a white rubber strap, and a strap made from recycled fishing nets.

Honestly? The white rubber strap is a winning combination. It creates a perfect contrast with the electric blue dial and accentuates that summery, nautical feel, even if you're wearing the watch in the middle of December.

Is it worth it?

The price is set at $12,300. That's about $500 more than the standard model. For this extra, you get exclusivity (only 50 pieces), a unique dial, and a ceramic bezel with orange accents, made especially for this edition.

If you're looking for a watch that's technically sophisticated, has a historical background, and looks completely different from anything your friends are wearing, this is a serious contender. That is, if you're quick enough to snag one of the fifty examples.

Technical data: Zenith Defy Extreme Diver Topper Edition