I didn't see this ad in Martijn's book, so I wanted to share it here. From a 1973 issue of Car & Driver.
The top copy reads, in part:
"Official autosporting watches used by Formula 1. World Champions, drivers, and serious competitors in North America and Europe now made available to auto enthusiasts by Chronosport -- the world's largest specialist watch company, Chronosport is the official support of watches and timing equipment to World F. 1. Champions Lotus, Can-Am McLarens, B.R.M., Brabham, March - and top U.S. and European race teams. ... "
As a Jet fanatic, I was intrigued by the inclusion of the MK III Jet in this "Drivers Watches" collection -- of course, because of the racing dial. Interestingly enough, the copywriter here makes no attempt to describe the Jet as a drivers or racing watch.
Good stuff.