Calibre 268 — the smooth-rim balance

In brief

Out went the screwed balance, in came a plain smooth ring. Everything else holds — 17 jewels, 18,000 vph, as across the 26x series — but this was the first of the two real technical changes that closed out this branch of the family.

Short history

Two technical steps define the last stretch of the 30T2 family. First came the move from a screwed balance to a smooth ring, around 1955, in the 268 and its centre-seconds equivalent the 285; then the switch to a flat hairspring with Novochoc shock protection, in the 269 and the 286. Omega set both out in its own technical guide of 1963.

Watches that used it

• Omega dress watches, mid-1950s