Vacheron Constantin Overseas Perpetual Calendar Ultra-Thin Skeleton with Sapphire Bezel (Ref. 4307V/220R-237C)

Vacheron Constantin Overseas Perpetual Calendar Ultra-Thin Skeleton Pink Gold (Ref. 4307V/220R-237C) - Price on Request

Every so often a watch comes through our doors that we almost never get to handle. This is one of them: the Overseas Perpetual Calendar Ultra-Thin Skeleton in rose gold, reference 4307V/220R-237C, with a fully skeletonized dial and a factory-set sapphire bezel. It is an off-catalog piece, rumored to be one of only five ever made, though Vacheron has never officially confirmed a number. We filmed it, weighed it, and shot it from every angle before it sold.

An Off-Catalog Overseas With a Sapphire Bezel

This is not your average Overseas. The base watch is the Overseas Perpetual Calendar Ultra-Thin Skeleton, and Vacheron has dressed it with a bezel of blue sapphires, gem-set into the 18k rose gold. Good gem-setting on a round case is one thing. Seeing it done cleanly on a bezel shaped like the Overseas, with its notched, six-sided profile, is another. The gold case measures 41.5 mm across with a lug-to-lug of roughly 49 mm, so it wears like a proper sports watch, but the sapphire bezel pushes it somewhere closer to jewelry.

The off-catalog Overseas Perpetual Calendar in rose gold, ref. 4307V/220R-237C.

A Skeletonized Perpetual Calendar Dial

The real story is the dial. The entire perpetual calendar is openworked, so you look straight through the movement from the front. Every bridge and gear sits out in the open. The calendar is laid out around the openwork: month and leap-year indication up top, the date read by a hand on the right, the day of the week over toward nine o'clock, and a blue moon phase down toward six. A perpetual calendar tracks the date, day, month, and leap years, so it does not need adjusting for the different month lengths, and the moon phase adds a second complication on top of it.

Month, date, day, and moon phase, all read through the openworked movement.

This is not a watch you read in the dark, and the lume leaves something to be desired. In daylight, though, it is more legible than a lot of openworked dials we handle, because the rose gold hands and applied markers carry enough contrast against the movement behind them.

The month and leap-year rings sit up top, with the pointer date scale to the right.

Ultra-Thin Caliber 1120 and a Sapphire Caseback

Behind the openwork is Vacheron's self-winding caliber 1120 QPSQ/1, the skeletonized perpetual calendar version of its ultra-thin 1120 base, with a 40-hour power reserve. The 1120 has real history: it grew out of the Jaeger-LeCoultre 920, the ultra-thin automatic that Audemars Piguet and Patek Philippe also built on decades ago. Vacheron finishes it by hand, and the openwork puts all of that finishing on display. Flip the watch over and the sapphire caseback gives you a full view of the movement and the openworked rotor. The gold rim around it is engraved "Vacheron Constantin," "4307V," and "Swiss Made."

The sapphire caseback opens onto the openworked movement and rotor.

Thin and Light on the Wrist

For a full perpetual calendar in solid gold, the proportions are impressive. The case comes in under 9 mm thick, genuinely slim for a skeletonized sports watch, and on our scale it weighed about 167 grams on the bracelet, just over a third of a pound. That is not heavy for solid rose gold, and it makes the Overseas easier to live with than the numbers suggest. Water resistance is rated to 50 m.

Under 9 mm thick, slim for a solid-gold perpetual calendar.

About 167 grams on the bracelet, weighed in-house.

On the wrist, the sapphire bezel and skeleton dial read as sporty and dressy at once.

At 41.5 mm on a 7-inch wrist, it sits flat and wears its size well.

What Comes in the Box

The watch arrives in Vacheron's Overseas presentation set, with the gray outer box holding a navy leather watch pouch and a matching zip travel pouch. The Overseas is built around interchangeable straps, so the set also includes the additional straps and the tool to swap them, letting the same watch move from the gold bracelet to leather or rubber.

The Overseas presentation set with its navy leather pouches.

Additional straps travel in the zip pouch, ready for a quick swap.

How Rare Is It?

This piece was never part of the standard Overseas catalog, and the sapphire-set bezel version is one we almost never see come through. It is rumored to be one of only five made, but that figure has never been officially confirmed, so we treat it as talk rather than fact. What we can say plainly is that we do not see these. Off-catalog Vacheron with a full gem-set bezel and a skeleton perpetual calendar is about as far off the beaten path as this brand goes. We sold this exact watch, and we would not expect another like it soon.

Specifications

FAQ

What is the reference number?

The full reference is 4307V/220R-237C. That is the off-catalog, sapphire-set bezel version of the Overseas Perpetual Calendar Ultra-Thin Skeleton in rose gold. The standard catalog version of this watch carries a different reference and a plain rose gold bezel, without the gem-setting seen here.

Does it have a display caseback?

Yes. The Overseas Perpetual Calendar uses a sapphire caseback, so you can see the openworked movement and its skeletonized rotor from the back. The gold rim around the crystal is engraved with the Vacheron Constantin name, the 4307V reference, and Swiss Made.

How thick and heavy is it?

The rose gold case measures 41.5 mm across and comes in under 9 mm thick, which is slim for a skeletonized perpetual calendar. On our scale the watch weighed about 167 grams on the bracelet, just over a third of a pound, so it wears lighter than most solid-gold sports watches.

How many were made?

It is rumored to be one of only five, but Vacheron Constantin has never officially confirmed a production number, so we treat that as talk rather than a documented figure. What we can say is that it was never a standard catalog piece, and we rarely see the sapphire-set bezel version come through.