with the launch of the tudor oyster collection in the mid-forties, the waterproof oyster case previously exclusive to rolex was added to tudor watches. this was followed by the tudor prince line in 1952, which was the first to be fitted with the self-winding rotor, also proprietary to rolex, and which became the foundation of the collection for the years to come. this same year, 26 tudor oyster princes were included in the british scientific expedition to greenland.