Reference 6536/1 and its brethren 6536 were in production for a short time between 1955 and 1959. They both feature the new calibre 1030, and the references have very minor differences with each other. Ref. 6536 features a slightly thicker case and slightly smaller dial diameter than ref. 6536/1. No certainty exists on why two such similar models have been sold at the same time. It is speculated that the more robust reference 6536 was targeted to a more professional market, while the more slender 6536/1 to the public at large.
On very early examples of these references, such as the present watch, the dial design is different: the depth rating is red and reads dimply “100/330”, without any meters/feet indication, and the finish is matte rather than gloss. Such dials are extremely rare and are considered absolute trophies. Furthermore, the dial on the present piece is absolutely unrestored and in exceptionally attractive condition. It furthermore features the correct crown with the cross symbol surmounted by the Rolex logo and bracelet dating from 1956.