

1983-Seiko-Catalog.V2, page 15
A compact JDM quartz dress line from around 1974, offered in tank and round shapes (including 18k-gold references such as the 2220 series) as part of the miniaturization era that followed Seiko's caliber-03 (1972), the first movement compact enough for a ladies' watch. A small dress-quartz sub-line rather than a documented world-first — coverage on priority sources is thin, so "firsts" claims warrant caution.