The Oyster Perpetual 28 and Oyster Perpetual 34 are covered by the Superlative Chronometer certification. This exclusive designation is issued to each watch leaving the Rolex workshops, attesting to its excellent performance on the wrist. This in-house certification is strictly controlled by internationally recognized, independent Swiss entities.
In 2026, the Superlative Chronometer certification has been strengthened with the addition of three new testing criteria: resistance to magnetism, reliability and sustainability. These criteria are implemented throughout the design and manufacturing stages of each timepiece – hundreds of checks and validations directly related to the watch’s performance are carried out during these phases. They supplement the criteria established when the certification was redefined in 2015 governing precision, waterproofness, self-winding and power reserve. That year, Rolex set up an exclusive testing protocol for its finished watches, conducted inside the manufacture on fully automated equipment. The precision requirements are particularly stringent: measured after casing the movement, the watch’s accuracy must be between –2 and +2 seconds per day. The rate deviation tolerated by the brand for the precision of a finished watch is significantly smaller than that accepted for official certification of the movement alone.
The Superlative Chronometer status is symbolized by the green seal that comes with every Rolex watch and is coupled with an international five-year guarantee.
