Bulova Super Compressor 'Jumbo', c. 1971

Dealer description — Analog/Shift

There are lots of Super Compressors out there, but few are truly exceptional. The JLC Deep Sea Alarm is one. The Universal Geneve Polerouter Sub is another. While Bulova's take on the distinctive dual-crown diver doesn't command the same kind of value, it manages to stand head and shoulders above other Super Compressors from other brands. The Super Compressor name refers to the innovative case design which utilizes a ‘compressor’ system designed to increase watertightness the deeper the watch dives under the water. As the atmospheric pressure increases, the case back compresses, pushing on the gaskets and creating a tighter seal. Despite the logic of the design, the compressor case wasn’t any better at preventing water intrusion than the garden variety screw-down crown — in fact, it was less effective in many models — but due to their good looks, compressor cases proved to be wildly popular during the 1960s. Eager to get into the burgeoning dive watch market, many of the best Swiss brands turned to EPSA (Ervin Piquerez, S.A.), the leading manufacturer of compressor cases at the time, for cases upon which to build their divers. So what’s so special about this Bulova? We’ve sold other Super Compressors,, but like 99% of examples out there, they were 36mm, the typical size for the era. Bulova produced a very small number of Jumbo Super Compressors, and they’re extremely rare (and sought after) today. The Jumbo's 42mm case feels appropriately hefty compared with the 36mm models, giving the watch the tool-like aspect it was always meant to have. This particular example features an aforementioned 42mm stainless steel Super Compressor case with an acrylic crystal, dual crowns, a gloss black Tritium dial with printed ‘Arabic’ indices, a matching ‘syringe’ handset, and an internal rotating dive timing bezel. Powered by the automatic Bulova Caliber 11ALAC movement and dating to circa 1971, it’s an awesome piece of horological history that doesn’t often surface. Nab this one before somebody else gets a similar idea!