THIRD SERIES TUDOR CHRONO
The Big Blocks were Tudor’s third series of chronographs. The first Big Blocks were launched in 1976 and there were a number of obvious aesthetic differences to previous chronographs. The most striking detail was the introduction of a third chronograph register on the dial - an hour indicator.
This watch features an early version of the 79170 dial, with the painted window around the date aperture and the beveled ends of the hour markers.
A FIRST FOR TUDOR
The biggest development was the introduction of an automatic movement making these watches the first self-winding chronographs from the Wilsdorf group and over a decade before Rolex introduced their first automatic Daytona chrono.
ALL ABOUT THE BEZELS
The 79170 is distinguished by the graduated 12-hour rotating bezel, used to measure elapsed time. There were three different bezel types on the Big Blocks, each with a different reference number.