The Watch:In the mid 1970's IWC produced tuning fork watches in two models. The first, Cal. 150, was date only and 24,600 were produced. The second, Cal. 160, had both a day and date, and 6,000 were produced. By vibrating hundreds of times per seconds, the tuning fork movement produces an extremely smooth second hand sweep. See the video above.
Both movements were made under license from Bulova by ESA in Switzerland, and often are considered the highest quality tuning fork movements ever made. 12 Jewels were used. They are 13 ligne movements (29.00 mm), with heights of 4.8mm and 5.5mm respectively.
The typical design of these watches was with a slight tonneau shape, like the Yacht Club, and with baton indices. The most "outrageous" of these 70s designs was the Edison model (using Cal. 160), seen here.
This example has recently been serviced and overhauled by IWC and comes with a certificate of authenticity from Geneva.
Condition: Excellent, pre-owned condition. Overhauled this year by IWC.
Includes:Watch, service papers, certificate of authenticity
