In 2022, Citizen brought back its 1977 Challenge Diver in two variants, the Promaster Mechanical Diver NB6021-68L with blue dial and metal bracelet, and the NB6021-17E with black dial and matching rubber strap (see WatchTime’s April issue from 2023 for an extensive introduction to the two versions that were available back then). While the original model from 1977 was water resistant to 150 meters, the Japanese watchmaker went with a 42-mm Super Titanium case for the modern interpretation, an increased water resistance of 200 meters, a sapphire crystal, a comparatively new in-house movement and a rather competitive price tag of currently $636 in the U.S. for the black dial version with black polyurethane strap.

“Inspired by the design of the 1977 Citizen Challenge Diver that was found on an Australian beach in 1983, the watch was covered in barnacles after having been submerged in the Pacific Ocean for years but was still ticking. That history has inspired our new Promaster Mechanical Diver and given it the affectionate nickname, Fujitsubo ? Japanese for barnacle.” Citizen Watch Company of America
Inside the titanium case, Citizen?s Cal. 9051 movement uses anti-magnetic materials for the balance spring and surrounding components to increase 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.? It should also be resistant ...