Seiko 45GS was in production approximately from 1968 to 1973, a run of approximately 5 years, carrying the 4520/4522 manual caliber in a 36.5 mm case rated to 50 meters.
The 44GS case language carried to a 36,000 vph hand-wound hi-beat - Daini's answer to Suwa's 61GS, with a VFA grade at the top.
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 Grand Seiko fraud is a polishing and parts story. The value of these watches lives in Zaratsu-polished planes and sharp ridge lines that a buffing wheel destroys in seconds, so over-restored cases are the market's default, not its exception. Beyond that: redials chase every textured and gilt variant, King Seiko donors supply lookalike parts, medallion casebacks get swapped onto lesser watches, and Special and VFA grade claims are movement facts that require movement photos. The serial dates the case to a month on Seiko's own system; the Seiko serial decoder on this site works for every reference in this family.
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.