Wakmann triple calendar, 3 register chronograph with Valjoux 730 movement. This is basically a Breitling that sold in the U.S. by it’s subsidiary Wakmann. Valjoux 730 was an improvement on Val. 72C which was used in Rolex watches in 1950s through 1970s. Val.730 beats at a higher rate. Movement serviced in Apr. 2013. This watch is cased in the Gigandet made case which measures 37 mm across. The gold filled case has never been polished after leaving the factory. There is some loss of chrome plating on the underside but this is not seen when the watch is on your wrist.
The button at 10 o’clock when depressed will change both Day and Month at the same time. So once you arrive at the desired month, move the hands until you arrive at the day previous to the one you want. Then with the button at 8 o’clock press repeatedly until you arrive at the date one day prior to the one you need. Now turn the hands past midnight and you will see both day and date will change. Set your exact time.
The buttons should not be operated when the hands are set between 9 P.M. and 3 a.m.