Little is known of the reference 6202 “Monometer” and it is rarely spoken of when discussing vintage Rolex sports watches, but despite all, it is perhaps one of the rarest and earliest Rolex sports watches to have ever been produced. As an experimental model launched by the brand, the moniker “Monometer” was trademarked in 1953 and the first examples appeared on the market the same year. The Monometer bore the same reference as the later “Turn-O-Graph”, 6202, and bears some aesthetic similarities to the early “Turn-O-Graph” that immediately followed it. It is unclear why Rolex chose the name at first and then discarded it for another, however there is no doubt that this timepiece, along with the Turn-O-Graph, were Rolex's first ever tool watches produced in series. With its rotating bezel calibrated to 60 units, the ground-breaking Monometer can be considered a major milestone that spearheaded over sixty years of dive watches at Rolex.

The present lot can only delight with its original black gloss dial and gilt printing. However, the rarity factor is further enhanced by the presence of the original pencil hour and minute hands, lollipop seconds hand and the unusual “Oyster Perpetual” printing between the 9 o’clock and 3 o’clock positions at the center of the dial. The present Monometer was most probably a prototype that was marketed and rapidly discontinued and replaced by the Turn-O-Graph. Some consider this the earliest Submariner, even though not officially carrying the name and housed in a 6202 case. The Monometer was made in exceedingly small quantities with two dial variants known – honeycomb or plain black lacquer, like the present lot.

Less than 10 Monometers are known to have appeared on the international auction market in the past 30 years, highlighting the extreme rarity of this piece. The present lot is in overall remarkable condition for a watch of its age, with a sharp, well-defined case, beautifully aged bezel that has turned to a burgundy tone, and an absolutely original dial. It is a prize for the collector of landmark references within the vintage Rolex pantheon, or vintage sports watches in general.