Released in 1981, the Cal. 4539 with design code 689 was part of Seiko's domestic market collection. Powered by the 4539 caliber with 35j jewels beating at 21,600 bph, it delivers a 58 hours power reserve. [seikata-wm-e4c2c4a2f81a]
Also known as: Sumo, Pogue
