El Primero has meant one thing since 1969: the world's first automatic high-frequency chronograph. Zenith built its identity on it. The tricompax dial layout is so tied to the Chronomaster name that most collectors picture it automatically.

The Zenith Chronomaster Solo Sport removes it.

What's left is the part that actually mattered all along, the 5Hz high-frequency architecture, in a 40mm steel case with a ceramic bezel and 200 metres of water resistance. It went on sale September 2, and at $9,800 for the no-date reference it's the cheapest way into the Chronomaster Sport family.

What the Calibre Actually Is

The El Primero 3620 is derived from the 3600 chronograph movement, with the chronograph works taken out and the high-frequency escapement left intact. It runs at 36,000 vph, or 5Hz, with a 60-hour power reserve.

That frequency is the whole point of El Primero. Five beats per second is what allowed the original to time to a tenth of a second in 1969, and it's what produces the notably smooth sweeping seconds hand. Strip away the pushers and subdials and the technical claim underneath is unchanged.

The 3620 isn't brand new to Zenith either. Versions of it already power the Defy Skyline and Defy Extreme Diver. What's new is putting it in a Chronomaster, which until now has been chronograph territory by definition.

Four References, All Ceramic

Every reference uses ceramic for both the rotating bezel and the dial:

• White ceramic dial, black ceramic bezel, sunray finished, with date - $10,900

• Black ceramic dial and bezel, polished, with date - $10,900

• Brown ceramic dial and bezel, polished, with date - $10,900

• Black ceramic dial, no date - $9,800

The brown is the outlier and the more interesting choice, warmer and less obvious than the monochrome pair. The no-date black is the one enthusiasts will argue for, both because a clean dial suits a time-only watch and because it saves $1,100.

The Spec Zenith Isn't Leading With

Buried in the details is 200 metres of water resistance, double what the standard Chronomaster Sport offers.

Combine that with a rotating bezel and lumed hour markers and you have something the Chronomaster line has never produced before: a watch you could reasonably treat as a diver. Zenith isn't marketing it that way, and the bezel is a minutes bezel rather than a dive scale, but the capability is there. For a collection built entirely around chronographs, that's a genuine change in what a Chronomaster can do.

The ZENCLASP

Zenith spent three years developing the clasp on this watch, which sounds excessive until you consider how often bracelet fit ruins an otherwise good watch.

The ZENCLASP offers tool-free micro-adjustment in 2.5mm increments across a total range of 10mm, adjusted on the wrist. Wrists swell through the day, in heat, after exercise, and 10mm of on-the-fly range covers that comfortably.

On-the-fly adjustment has been spreading across the industry for a few years now, from Tudor's T-fit to Seiko's micro-adjust clasp. Zenith arriving later with a wider adjustment range is a reasonable trade.

Where This Sits

At $9,800, the no-date Solo Sport is one of very few current Zenith references under ten thousand dollars, and the only Chronomaster Sport that clears that bar. The steel chronograph version runs closer to $11,200.

The proposition is straightforward: you're paying for the movement architecture and the manufacture name rather than the complication. Whether that's compelling depends on how much you actually use a chronograph, which for most owners is rarely.

What you get instead is a genuinely versatile watch. Forty millimetres, ceramic construction that won't scratch the way steel does, 200 metres of water resistance, a bezel you can time with, and a movement that beats faster than almost anything else at the price. That's a watch with a wider range of use than the chronograph it's derived from.

For anyone weighing a high-frequency Swiss movement against other options in the category, Watch Gang's Swiss automatic selection covers the range at several price points, and the broader sport watch collection is worth a look if versatility is what's drawing you here.