The 70xx line is in general simpler than the line 61xx, not having some sophistications as hack and the calendar quick-set pressing the crown. Beyond less sophisticated, the 70xx line have on a lesser number of variants. This is mainly because of the arrival of the "quartz age". Seiko, pioneer in this technology, deviated its efforts for this promising technology. Therefore, the 70xx line did not have the chance to have more complicated variants, nor to equip the Grand Seiko collection, that was abandoned during the 70's, for the same mentioned reason. The noblest variants are the chronographs.
