The vintage Grand Seiko era complete: from the 1960 original, built to prove a chronometer standard, to the mid-70s quartz interruption. Eight references across two competing factories - Suwa's line through the Self-Daters and the hi-beat automatics, Daini's through the Grammar of Design watches - rendered as the three short lineages they actually were.
| REFERENCE | PRODUCED | CALIBER | CASE | RATED |
|---|---|---|---|---|
| Seiko 3180 "Grand Seiko First"KEY | c. 1960–1963 | 3180 (5720A) | 35 mm | 30 m |
| Seiko 43999 "Self-Dater" | c. 1963–1966 | 430 | 36.5 mm | 50 m |
| Seiko 5722 "Self-Dater" | c. 1966–1968 | 5722A/5722B | 36.5 mm | 50 m |
| Seiko 44GSKEY | c. 1967–1968 | 4420B | 36.5 mm | 50 m |
| Seiko 45GS | c. 1968–1973 | 4520/4522 | 36.5 mm | 50 m |
| Seiko 62GSKEY | c. 1966–1968 | 6245/6246 | 37 mm | 50 m |
| Seiko 61GSKEY | c. 1968–1975 | 6145/6146 | 36.5 mm | 50 m |
| Seiko 56GS | c. 1970–1975 | 5641/5645/5646 | 37 mm | 50 m |
"c." marks a production window documented as approximate — including by Seiko's own archive.