The “Small Daytona” was produced in 1965 and was the first waterproof Cosmograph model Rolex created. This timepiece is distinguished by its screw-down crown and ‘Millerighe’ pushers. The Ref. 6240 had a brief production period from 1965 to 1969, making this 1966 model one of the less than 2000 examples Rolex ever produced.