FS: Vintage Grand Seiko 56GS Case 36.5mm - 5645-7010 (1971 Date Only) and 5646-7010 (1973 Day-Date) Gold Cap

5645-7010 Video: 5646-7010 Video: For sale are two vintage 1970s Grand Seiko 56GS case models, both gold capped versions. The 56GS was introduced in 1970 to meet demand for slimmer automatic movements, achieved through development of the 56 series movements which were just 4.5mm tall. Another benefit was improved reliability over the earlier 36000bph models. Presented here are the 5645-7010 model, a date-only reference, and the 5646-7010 model, day-dat...