This is another version of the Big Bubbleback ref 5075 with straight lugs from the year 1947. The watch must have been serviced in the late 1950s or early 1960s with a replacement of dial. The size is 36mm. The date alternate between red and black.
This is another versions of the Big bubbleback. There are several generations of the so called Big Bubbleback namely : Rolex 4467 ( from year 1945-1949) caliber 745, only in solid gold, Rolex 5030 (solid gold) 5031 (Steel and gold) 5075, 6031 (from year 1