Released in 1989, the Cal. 6637 with design code 473 was part of Seiko's domestic market collection. Powered by the 6637 caliber with 29j jewels beating at 21,600 bph, it delivers a 47 hours power reserve. [seikata-wm-e1b5d4afa4d1]
Also known as: Shogun, Baby Tuna
