Omega 166.024 was in production approximately from 1966 to 1970, a run of approximately 4 years, carrying the 565 automatic caliber in a 42 mm case rated to 200 meters.
The 165.024's date-equipped sibling, not its successor: same case, same era, a calendar at three, sold alongside the no-date to the end of the line.
Dates carry a "c." because that is what honesty requires: Seiko's own archive gives only approximate production windows by caliber, so the file states the documented range and marks it as such rather than inventing precision.
The full collector's file for this reference — variants, dial codes, and the authentication walk-through — is on the writing schedule; the specifications above are the permanent record.
Vintage Seamaster 300 fraud is a parts story on a valuable case. The reference interchanges freely with lesser Seamasters of its era, so redials, relumes, service bezels, and swapped broad-arrow hands are the market's default condition, and military engravings are the easiest forgery of all, which is why issue watches are provenance purchases first and metal second. The rules: the dial and lume must age as a set, the bezel and hands must belong to the serial's documented window, bakelite originality claims carry the burden of proof, and the Omega serial lookup on this site dates every movement in this family, with the usual caveat that the serial dates the movement, not the parts around it.
Production windows and specifications compiled from documented collector references and period catalogs, cross-checked across independent sources; manufacturer records for this era are approximate by Seiko's own account.