Zodiac has just announced its release of the new Sea-Chron dive chronograph. A staple model in the brand’s 1960s catalog, the Sea-Chron followed the success of the original Sea Wolf diver. It’s also no coincidence that dive watches saw a boom in demand in the early ’60s. During this decade, diving went from a niche endeavor for a brave minority to a commercialized one. As the underwater world became accessible to the masses, the dive watch — an essential piece of diving equipment back then — grew in popularity. Brands got brave and started creating many iterations of the basic diver. Adding a chronograph complication was one of the many ways that brands enhanced the functionality of these tool watches. Today, it’s a mix of their function-informed looks and a retrospective romantic vision that fuels the undying inertia of the appeal of such watches.

Take a look back at the original Zodiac Sea-Chron. I think you’ll agree it was about time it made a comeback. The folks at Zodiac came to the same conclusion. Today, the modern reissue of the Zodiac Sea-Chron is finally here in two different colorways. Instead of opting for a 1:1 reissue of the watch, the brand has introduced some changes. Some are subtle, but others are rather bold. These primarily affect the dimensions. But the dial, bezel, crystal, and movement are also different. When I say it’s a new watch, I mean it. It may look like the Sea-Chron that collectors know and love, but it’s well and truly a whole new beast.

Zodiac Sea-Chron dive chronograph

The new Zodiac Sea-Chron dive chronograph

A blast from the past, the new Zodiac Sea-Chron diver is back from the brand’s archives. It seems to have been pumping iron throughout its hiatus from production because the new version comes in at heavyweight proportions. The 2023 Sea-Chron measures 42mm in diameter and has a lug spacing of 20mm (so far, so good). It stands tall at 16.5mm and has plenty of wrist presence at 50.5mm from lug to lug. It gives the classic Omega Seamaster 300M Chronograph reference 2599.80.00 a run for its money (41.5mm × 16.2mm × 49mm). And it only comes in slightly smaller than the contemporary Omega dive chronograph reference (44mm × 17.2mm × 52.2mm). You get the point; the thing is chunky!

Perhaps it’s wearable in person, but I feel these dimensions will raise an eyebrow or two. Especially bearing in mind that the original vintage Sea-Chron was 39mm in diameter and 12.5mm thick (I have not found information on the lug-to-lug). That said, in the press images, it appears to wear rather well thanks to the downward-curved lugs. As someone who is both very much in touch with the online watch community (namely on Instagram) and an avid consumer of watch media, I begin to sense the early rumblings of a shift in taste. Perhaps it’s a slowly growing fatigue of “smaller” watches, or maybe it’s all in the cyclical nature of these things. It could also be just a minority uprising of anti-mainstream contrarians. Regardless, I think there’s always space for a more oversized watch in any collection (within reason, of course).

Zodiac Sea-Chron dive chronograph

Beyond dimensions

So, other than the size, what else is new? Well, if we look at the dial, you’ll notice that the flat matte dial of the original is no more. Instead, a multi-level dial with several finishes takes its place. The central dial has a sunray finish, and the recessed sub-dials have a classic radial texture. Additionally, the lume markers are recessed instead of painted, giving it the feel of a classic sandwich dial. As in the original, the Zodiac logo and Sea-Chron name are printed onto the dial without an applied logo. Instead of the original’s “20 atm.” text above the 6 o’clock register, you’ll find the depth rating in meters and feet.

The diving bezel maintains the original’s markings (with only the first 20 minutes fully graduated). This time, polished ceramic takes the place of fade-prone anodized aluminum. Finally, the movement, an automatic Sellita SW510 b, allows for the same chronograph layout as the original’s Valjoux 72. With a 30-minute register at 3, a 12-hour register at 6, and running seconds at 9 o’clock, it’s (I find) one of the most useable chronograph layouts.

Zodiac Sea-Chron dive chronograph

Final thoughts

A cult classic and collector’s darling shows its face on the watch market once again. Zodiac has brought back one of the most charming, underrated dive chronographs ever made, and I, for one, could not be more excited about the return of the Sea-Chron. Though I’ll reserve my thoughts on the size and wearability of the watch for the hands-on review, I must say I was a bit put off when I first read the press release. I’m all for a chunky dive watch. But when dealing with a reissue of a vintage piece, I feel that it pays off to stay closer to the original dimensions.

When you consider the fact that the Valjoux 72 movement used in the original from the ’60s is only 0.95mm thinner than the Sellita SW510 in the 2023 model and that both watches are rated to 200m of water resistance, you can’t help but wonder what exactly accounts for the extra thickness. Was the formula for making a slim chronograph truly lost to time? Or is there any hope for a modern, affordable, slim chronograph? Considering that the new Sea-Chron is automatic rather than hand-winding, I can cut it some slack, but four extra millimeters seems a bit excessive. That said, I’m still excited to get my hands on it, run it through its paces, and report back.

The new Zodiac Sea-Chron dive chronograph is available starting today. You can find it online on the Zodiac website and at any of the brand’s authorized retailers. Both the panda and blue and black models are priced at US$2,495 (about €2,260). For more information, please visit the Zodiac website.

Watch specifications

ZO3604 / ZO3605
Sunray-brushed blue and black or black and white dial
Case Material
Stainless steel
Case Dimensions
42mm × 16.5mm × 50.5mm
Sapphire crystal
Case Back
Solid steel case back
Sellita SW510 b — automatic winding, 28,800vph frequency, extended power reserve of 72 hours
Water Resistance
Stainless steel five-link bracelet (20mm) with dual-deployant clasp and spring-loaded extension
Time, 12-hour chronograph, 60-minute timing bezel