In the 1930s, Rolex developed the world's first automatic movement, the "Perpetual." Because this was designed by layering an automatic winding unit onto a manual winding movement of the time, the movement inevitably became thicker. The Bubble Back, with a case back that bulged like a bubble, was born to accommodate this.
Later, models appeared that reduced the thickness by increasing the diameter of the movement. This is the so-called Semi-Bubble Back that we are introducing today.
In the past year or two, the Bubble Back has been gaining particular attention among enthusiasts, but its case size of around 30mm and antiquated dial design are not necessarily universally appealing.
The Semi-Bubble Back is the final version of the Bubble Back, offering a unique twist that allows one to enjoy the characteristic bulging case shape of the Bubble Back with a case diameter that isn't too small.
Wedge-shaped indexes, alpha hands, engine-turned bezel—all are vintage-specific details. The moderately aged dial is in a very satisfying condition.
While it's rare to find vintage watches in good condition, the condition of both the dials and cases of these two pieces is impeccable. Especially with Bubble Backs, it's crucial that the case hasn't been excessively polished to appreciate its volume, and both of these retain their original shape sufficiently.
Both references are Ref. 6085. There's also the similar Ref. 6084 with a smooth bezel, but perhaps the engine-turned bezel is rarer. Personally, I prefer the latter.
The case is the Super Oyster Case, adopted only during that period. It uses a different crown than the screw-down type found on many Rolex watches, including current models, and you can see "SUPER OYSTER" inscribed on the crown along with the crown logo.
Among the various case materials such as K9, K10, and K14, the K18YG presented here is the most sought after.
(Top) Crown with rich information unique to the Super Oyster Case
(Bottom) Model with a very rare bracelet
Furthermore, one of the two pieces is a bracelet specification that was sold at the time. This bracelet, presumed to have circulated in the European market, features rare original straight end links and a numbered engraving on the inside of the clasp. With a lug width of 19mm, it can also be fitted to pre-Daytonas and Kylies, so many people are looking for it, but the chance of finding it as a standalone part is almost nil.
The combination of vintage wedge-shaped indexes and alpha hands is undoubtedly in excellent balance, and the sharp dial combined with the plump, substantial case creates a unique Semi-Bubble Back. It's rare to find such pieces with no complaints about condition or material.
This is a somewhat artful compromise, a suggestion for enjoying vintage more steadily while acknowledging the enthusiasm of Bubble Back enthusiasts.
*The model with the bracelet has, thanks to you, sold out.
LEATHER STRAP
BRACELET
