Herology on Twitter: "1975 Seiko 6139-8020 “Hexagon” 17 Jewels Chronograph around 39mm wide w/c and 12mm thick which makes this “Speed Timer” much more compact compared to the venerable “Pogue.” 👍👍👍 #Seiko #
Seiko Chronograph Automatic Ref No. 6139-8020 for $462 for sale from a Seller on Chrono24
6139-8020 Questions About Original Dial & Hands | The Watch Site
1972 Seiko Chronograph ref. 6139-8020 black and blue dial - TIMELINE.WATCH collection
SEIKO 6139 8020 CHRONOGRAPH ORIGINAL SILVER DIAL 8040T RARE RALLY SPORT BRACELET | WatchCharts
Seiko 6139-8020 Chronograph Watch *1975* Men 6139B Working | WatchCharts