The B31 caliber took four years to develop, and upon its debut, it garnered an unprecedented level of attention. First and foremost, the movement measures 28 millimeters in diameter and 4.8 millimeters in thickness—dimensions that are not only smaller and thinner than those of the B20, but, more importantly, allow it to perfectly fit into any watch case size ranging from 38mm to 44mm. In terms of performance, the movement operates at a frequency of 28,800 vibrations per hour and boasts a power reserve of up to 78 hours. Beyond merely passing Swiss Chronometer certification—which limits daily rate deviation to between -4 and +6 seconds—it has also undergone a rigorous 16-year accelerated aging simulation test established by Breitling specifically for its in-house movements; a standard far exceeding industry norms. During this grueling test, the crown is subjected to 100,000 winding cycles to ensure the durability of the gear train; the oscillating weight undergoes 3,456,000 rotations to evaluate automatic winding efficiency; and finally, the movement endures 60,000 shocks of 500 Gs to verify its shock resistance, thereby ultimately guaranteeing its long-term, stable operation even in extreme environments, replica Breitling Superocean price.
In addition to its exceptional performance, the movement is equally remarkable in terms of decoration. It features a beautifully skeletonized oscillating weight, while its bridges and mainplate are exquisitely finished with Geneva stripes and perlage, respectively. Beyond its aesthetic appeal and performance capabilities, the movement's greatest highlight is its use of a free-sprung balance wheel with weights—a feature rarely seen in this class of timepieces. The primary advantage of a free-sprung system is that, during regulation, there is no longer a need to adjust the delicate hairspring using a regulator index; instead, one simply adjusts the weights on the balance wheel itself, ensuring a more accurate and stable regulation process. Furthermore—aside from the movement's practical thickness—the introduction of a 40mm case diameter to this series for the very first time comes as a delightful surprise. Personally, I believe that 40mm represents the absolute perfect size for a dive watch—a point amply demonstrated by iconic models of the past, such as the original "Submariner," and modern limited editions like the classic "Fifty Fathoms."
