Citizen Promaster Dive Automatic “Fujitsubo:” Designed for Persistence

This article was originally published in the Design 2023 Issue of the WatchTime print magazine.

The Japanese brand’s archives contain a fascinating story about a lost (and found) dive watch: In 1983, a Citizen Challenge Diver was found on a beach in Australia. The watch was covered in barnacles after having been submerged in the Pacific Ocean, but the movement inside had remained protected from the seawater and was still ticking. The number of barnacles attached to the watch indicated that it had been in the ocean for a number of years.

For 2022, Citizen has brought back two new versions (the NB6021-68L with blue dial and bracelet, and the NB6021-17E with black dial and strap) of the “Fujitsubo” nicknamed classic (meaning “barnacle” in Japanese). They unmistakably take design cues from the original Challenge Diver design (like the embossed indices and the classic green lume), but their external features and the movement inside have been massively updated: The sapphire crystal has a flat cut top and a domed underside, and the sides are beveled to provide a thick, retro look. The new version comes with the same 41-mm diameter as the original model, the case, however, is made of lightweight, scratch-resistant Super Titanium, and is thinner than the original model to ensure a more comfortable fit on the wrist. The brand’s proprietary space-age material is 5 times more scratch resistant and 40 percent lighter than stainless steel. Citizen had introduced the world’s first watch made of solid titanium in 1970, a material that is light, antiallergic and corrosion-resistant, and later developed Super Titanium.

Inside the case, Citizen’s new Cal. 9051 movement (regulated to a daily accuracy of -10 to +20 seconds) uses anti-magnetic materials for the balance spring and surrounding components to boost the magnetic resistance of the watch. According to Citizen, the movement maintains its performance “even when placed 1 centimeter from a device emitting a magnetic field of 16,000 A/m.” Both watches are also resistant to magnetic fields from everyday devices, including smartphones, and they can even be used aboard ships with magnetic compasses. Last but not least, the new Promaster watch is also an ISO compliant dive watch up to 200 meters (and assumingly even more barnacle-proof than its predecessor).

In short, an already timeless design has now been updated with the brand’s most modern mechanical innovations.

Citizen Promaster Dive Automatic “Fujitsubo” Specs:

Manufacturer: Citizen Watch Co., Ltd., 6-1-12, Tanashi-cho, Nishi-Tokyo-shi, Tokyo 188-8511, Japan

Reference number: NB6021-68L (with blue dial and bracelet), NB6021-17E (with black dial and strap) 

Functions: Hours, minutes, seconds, date 

Movement: Caliber 9051, automatic, -10/+20 seconds per day, approx. 42 hours power reserve (when fully wound), 28,800 vph, 24 jewels 

Case: Super Titanium with Duratect TIC, aluminum bezel insert, sapphire crystal, 200-meter water resistance 

Bracelet and clasp: Super Titanium or urethane (24-mm width), folding clasp or pin buckle 

Dimensions: Diameter = 41 mm, height = 12.3 mm 

Price: $795 (NB6021-17E), $995

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