Rather than a typical balance wheel, it used a tuning fork (visible in the open-work dial), powered by a one-transistor electronic oscillator and a 1.55v battery - delivering an oscillating rate nearly 150 times faster than that of a typical mechanical watch.
It was nicknamed the Spaceview for its green colour scheme and ‘circuit board’ dial.
A new ‘heritage’ version of this watch came out a couple of years ago but it is still possible to buy an original for less. This 14ct gold example from c.1965 has a guide of $200-400 when Turner Auctions + Appraisals in San Francisco sells a single-owner collection of vintage wristwatches on March 24.
Vintage Watches: One Man’s Collection features over 140 predominantly mid-century timepieces from a private collection in northern California.