Seiko -“Calculator” Slide Rule Automatic Chronograph Wrist Watch - 6138-7000- Men - 1970-1979 in Turkey
SRP611K] I get more comments on this watch than any other - my trusty Seiko 5 Pilot watch with a slide rule, powered by 4R36 auto with hack/wind. 45mmx13mm. Matched with a
SEIKO CALCULATOR 6138-7000 5 SLIDE RULE BLACK (1689 | eBay