California-based Topper Jewelers has been on an absolute roll to close out 2025, first with a fully-lumed “Great White” edition of DOXA’s SUB 250T GMT diver, and now with one of the best-looking Zenith watches we’ve ever seen — and that would be a pretty long list.
Zenith’s Return to the Depths
For a manufacture that spent decades away from dive watches, Zenith has been making up for lost time in impressive fashion. The Defy Extreme Diver, which debuted at Watches & Wonders 2024, represents the brand’s modern take on its original 1969 Defy Diver — a 600-meter-rated beast that helped establish Zenith’s credentials in the professional diving space back when the space race was still hot news. That vintage reference (the A3648) featured the robust construction and precision that Zenith built its reputation on, with double seals and shock resistance that were ahead of their time.
This new Topper Edition takes that heritage and adds something we haven’t seen before with a lume treatment that actually looks like nature’s glow instead of just glowing in the dark. Tiny specs of Super-LumiNova are scattered across the dial like bioluminescent plankton, creating a magnificent effect. When the lights drop, the watch transforms into something that literally feels like it was found on the ocean floor.
Technical Execution
The 42.5mm titanium case is lightweight despite maintaining a 600m depth rating and helium escape valve for saturation diving. Zenith’s decision to strip out the date function on this version was the right call — the El Primero 3620 movement inside runs at a high-beat 36,000 VpH, and the cleaner dial lets the wave texture and scattered lume take center stage. The bright blue rotor visible through the caseback sticks with the whole ocean theme as well.
That wave-textured dial in brilliant blue is complemented by a ceramic bezel insert that Zenith produced specifically for this collaboration, finished with orange Super-LumiNova at the five-minute intervals. The indices and hands glow green, while the minute hand glows blue to match the bezel pip.
Zenith’s tool-free quick-change strap system remains one of the better implementations we’ve seen, and this watch ships with the integrated titanium bracelet plus white rubber and recycled fishing net straps. However, the white rubber option might be the best pick as it plays well against that electric blue dial.
Spec Sheet
Model: Defy Extreme Diver “Bioluminescence” Topper Limited Edition
Case Material: Titanium
Case Size: 42.5mm
Case Thickness: 15.5mm
Movement: Zenith El Primero 3620
Water Resistance: 600m
Bezel: Blue ceramic unidirectional, Super-LumiNova markers
Dial: Blue wave texture with scattered Super-LumiNova specs
Lume: Super-LumiNova SLN C1 (green emission on indices/hands, blue on minute hand, orange on bezel)
Straps: Integrated titanium bracelet, white rubber strap, recycled fishing net fabric strap
Limited Edition: 50 pieces
Price: $12,300
Pricing & Availability
The Zenith Defy Extreme Diver Topper Edition is available now exclusively through Topper Jewelers for $12,300 — a $500 premium over the standard model — with just 50 pieces in the run.
Recap
Zenith Defy Extreme Diver Topper Edition
Topper Jewelers just dropped another killer collaboration with Zenith — a 50-piece limited edition of the Defy Extreme Diver that features a scattered lume treatment mimicking bioluminescent plankton, along with a wave-textured blue dial that transforms the typically utilitarian diver into something surprisingly elegant.
