Grand SeikoHistorical Collection Self-Dater Spring Drive Platinum Limited Edition

From the retailer listing

In 1964, the 2nd generation of Grand Seiko was released. Manufactured at Suwa Seikosha (now Seiko Epson), the Grand Seiko Self-Dater was the 1st model of Grand Seiko not only to use a date display, but also water resistance and to use the Zaratsu polishing technique. For the 50th Anniversary of this model, Seiko has introduced 3 Spring Drive models, and 2 quartz models to commemorate this piece as a part of their Historical Collection. Also made at their Suwa facility, Shinshu Watch Studio, these limited editions feature higher accuracy calibers, the 9R15 for Spring Drive rating at +/- 10 seconds a month, and the Quartz 9F82 with +/- 5 seconds a year, both utilizing specially selected quartz crystals to ensure higher accuracy. These pieces symbolize the "Evolution of Practicality". Caliber: 9R15 Drive system: Spring Drive Case Material: Platinum 950 Case Back: See-through screw case back