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Seiko 5C20-6020 Watch Guide

The Seiko 5C20-6020 is a watch model based on the 5C20 movement.

Parts List

250N02GN00crystal - crystal
30M22NA1crown - crown
0H2520Ncase back gasket

Caliber 5C20

Caliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual page

Other models with the same movement

5C20-5000
5C20-5010
5C20-5020
5C20-5030
5C20-5040
5C20-6000
5C20-6009
5C20-6010

About “The Seiko Guy”

Hey, nice to see you here!
My name is Andrea Secco, I’m a watch enthusiast and a Seiko collector.
I hope this website will be useful to all of you who share this passion.

Andrea Secco

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Recent Posts

  • Where are Seiko watches made?
  • King Seiko VANAC
  • Seiko Lord MarvelSeiko Lord Marvel
  • Seiko WatchesThe History of Seiko Wristwatches
  • Seiko Five SportsHistory of the Seiko 5 Sports
The Seiko Guy

the_seiko_guy

The journey of a watch enthusiast into the past, present and future of Seiko. 🇮🇹🇯🇵
Back in the late ’70s, Seiko introduced the Slim Back in the late ’70s, Seiko introduced the Slim Turtle divers with a brand-new case design that quickly became an icon for the Japanese brand. The “Slim Case” went on to feature in many dive watch series before becoming the go-to standard for the 5 Sports line starting in 2019. But over time, this case design also popped up in some lesser-known models that many seem to have forgotten—like these three gems right here. From left to right: the Seiko Alpinist SARB063 (limited to 500 pieces), the Subaru limited edition (360 pieces), and the WENA Premium Black (300 pieces). #seiko #seikoskx #seikoslimturtle #seikoslimcase #seiko5sports #seikodiver #seikowatches #seikoalpinist
Nobody seems to remember the Seiko Transocean and Nobody seems to remember the Seiko Transocean and the Mohawk. Do you think Seiko has abandoned them for good, or might we see a revival someday? #seikodiver #seiko #diverswatch #seikoprospex #seikowatches
Where are Seiko watches made? https://www.theseiko Where are Seiko watches made? https://www.theseikoguy.com/where-are-seiko-watches-made/ (link also in bio) The production dynamics in watchmaking, both in Japan and elsewhere, are highly complex and have been a topic of considerable debate, particularly since it became common practice for companies to shift part of their manufacturing to countries with lower costs. In this article, I’ll delve into where and how Seiko Group watches are produced, and I’ll explain the differences between “Made in Japan” models and those that aren’t.
King Seiko Vanac complete guide https://www.thesei King Seiko Vanac complete guide https://www.theseikoguy.com/king-seiko-vanac/ (link also in bio)
Seiko small size automatic diver’s watches. Seiko small size automatic diver’s watches.
The Seiko Lord Marvel complete guide https://www.t The Seiko Lord Marvel complete guide https://www.theseikoguy.com/seiko-lord-marvel/ (link also in bio)
Seiko Diver Buddy. #seikodiver #seikowatch #seiko Seiko Diver Buddy. #seikodiver #seikowatch #seiko
Seiko vintage chronographs. Seiko vintage chronographs.
Seiko King Quartz LL (Long Life) ref. QHD010 and Q Seiko King Quartz LL (Long Life) ref. QHD010 and QHD020. Introduced in January 1977, featuring a 5-year battery life and an accuracy of ±10 seconds per month. #seiko #seikocollector #watches
Seiko Suwa and Daini automatic chronographs. 🐼 Seiko Suwa and Daini automatic chronographs. 🐼 #seikowatches #seikochronograph #seikopanda #vintageseiko #seikosha #seiko
Seiko 6139-6000 from February and March 1969. Whil Seiko 6139-6000 from February and March 1969. While Zenith was presenting its prototype, Seiko was already mass-producing the first automatic chronographs in history. #seiko #seiko6139 #automaticchronograph #seikowatches #zenithelprimero #vintageseiko #seikopogue #watchcollection
Seiko “Arcobaleno” 7002-8000. #seikoitalia #s Seiko “Arcobaleno” 7002-8000. #seikoitalia #seikowatches #seikoarcobaleno
It has been five years since I became passionate a It has been five years since I became passionate about Seiko watches and the long history of this Japanese brand. Beyond the watches I collect, there is another aspect that is just as important to me: researching information and, in particular, documenting the past. This is part of my Seiko library, which includes, from top to bottom: - Old and new books about the brand, its history, and the history of the Hattori family; - Over half a century of annual catalogs (the collection is nearly complete, with only a few volumes missing); - Decades of “Seiko News” volumes, which provided monthly updates on new releases for Japanese retailers. In addition to all this, I have gathered dozens of internal publications, price lists, and vintage product catalogs, along with a vast collection of technical documents on watches and movements. Much of this material is extremely rare and difficult to find. Assembling it all has been a long journey, but these resources are invaluable for understanding both the past and present of Seiko and Japanese watchmaking. #seiko #seikowatches #japanesewatches #grandseiko #seikosha #kingseiko #vintageseiko
King Seiko VANAC (1970s) #kingseiko #vintageseiko King Seiko VANAC (1970s) #kingseiko #vintageseiko #seikosha #seikowatches #vanac
Seiko Actus SilverWave vintage watch, 6306 automat Seiko Actus SilverWave vintage watch, 6306 automatic movement.
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This website is the work of a watch enthusiast and a collector of Seiko and Grand Seiko timepieces, and it is not affiliated with Seiko in any way.

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