Calibre 266 — 17 jewels and antimagnetism settled

In brief

By 1950 the sub-seconds branch had a settled standard, and the 266 is it: 17 jewels, antimagnetic construction and the 18,000 vph shared by every 30 mm calibre in the family. A year after the renumbering, the shape of the 26x series was fixed.

Short history

Barely a year after the reorganisation of 1949, the 266 arrived with the improvements Omega had been feeding into the sub-seconds branch of the 30T2 family already in place — 17 jewels, antimagnetic construction. It is also one of the few calibres here with a verified movement photograph, so the finishing and the bridge layout typical of this generation can be judged directly.

Watches that used it

• Omega dress watches, mid-1950s