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Seiko 8Y21-0040 Watch Guide

The Seiko 8Y21-0040 is a watch model based on the 8Y21 movement.

Parts List

DH0115B01case back gasket - crown and stem gasket

Caliber 8Y21

Caliber manual pageCaliber manual pageCaliber manual pageCaliber manual pageCaliber manual page

Other models with the same movement

8Y21-0010
8Y21-0019
8Y21-0020
8Y21-0021
8Y21-0029
8Y21-0030
8Y21-0050
8Y21-0060
8Y21-5000
8Y21-5010
8Y21-5020
8Y21-5029
8Y21-5030
8Y21-5040
8Y21-5050
8Y21-5069
8Y21-5070
8Y21-5071
8Y21-5079
8Y21-5080
8Y21-5090
8Y21-509A
8Y21-5100
8Y21-510A
8Y21-5110
8Y21-5120
8Y21-512A

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

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Seiko Lord Marvel first model from 1958, gold-fill Seiko Lord Marvel first model from 1958, gold-filled case. This is the first dial version, featuring no SD logo. #seiko #lordmarvel #seikolordmarvel #seikowatch #vintageseiko #watches #japan #luxurywatch
Seiko Laurel Dust Proof NO.CEM-4. No case code and Seiko Laurel Dust Proof NO.CEM-4. No case code and no serial number. #seiko #vintageseiko #watches #seikowatch #seikocollector #seikofam
Seiko Sportsman Dolphin, Water Protected J13035. Seiko Sportsman Dolphin, Water Protected J13035. #seiko #vintageseiko #seikowatch #watches #seikofam
The Seiko Pikachu ⚡️ #seiko #tokyo #japan #gi The Seiko Pikachu ⚡️ #seiko #tokyo #japan #giappotour #giorgiovanni #seikowatch #seiko5sports #pikachu #pokemon #watches
Seiko 38SQW 010 and 014 with their original bracel Seiko 38SQW 010 and 014 with their original bracelets! As is often the case with quartz models from the 38 series, they were sold as “non-working” watches, but all it took was a simple battery replacement to get them running flawlessly. To this day, I don’t think I’ve ever come across a single non-functional watch from the 38 series, a true testament to the incredible quality of these quartz movements, still accurate after more than 50 years. #seiko #watches #vintageseiko #seiko38sq #seikoquartz #vintagequartzwatches #seikowatch
The latest Seiko Quartz I’ve added to my collect The latest Seiko Quartz I’ve added to my collection. A beautiful watch from the 38 family, dating back to the first half of the 1970s, featuring a stunning “Snowflake” dial. It houses a spectacular movement, often overlooked by those who don’t truly understand watches, simply because it falls into the quartz category. These models were positioned above most Grand Seikos of their time, and this was reflected in both their build and finishing quality, as well as their price. #seiko #watches #seikowatch #vintageseiko #seikoquartz #luxurywatch #grandseiko #watchfam
Seiko pre-WW2 ladies wristwatches in solid gold. M Seiko pre-WW2 ladies wristwatches in solid gold. Manual winding 5-ligne movements. #seiko #vintageseiko #seikosha #watches #seikowatch
Vintage Seiko Quartz #watches #seiko #grandseiko Vintage Seiko Quartz #watches #seiko #grandseiko #seikoquartzastron #quartzastron #35sq #grandquartz #twinquartz #vintageseiko #watchcollector
Seiko McDonald’s commemorative watch. #seiko #w Seiko McDonald’s commemorative watch. #seiko #watches #seikowatch #mcdonalds #japan #vintageseiko
Seiko Wena “Premium Black” 300 Limited Edition Seiko Wena “Premium Black” 300 Limited Edition. Mechanical watch head, electronic smart bracelet. This watch is part of a variety of Slim Case models that Seiko introduced shortly before the launch of the new 5 Sports series. #seikowatch #seikowena #seiko #slimcase #slimturtle #seiko5sports #seikofamily #watchesofinstagram
Grand Seiko Toshiba (5641-7000) and Idemitsu (5645 Grand Seiko Toshiba (5641-7000) and Idemitsu (5645-7000) commemorative editions. #grandseiko #seiko #watches #grandseikowatches #hibeat #vintagegrandseiko #theseikoguy #watchcollector
Seiko MarineMaster 300 Hi-Beat and Naomi Uemura. Seiko MarineMaster 300 Hi-Beat and Naomi Uemura. #seiko #seikomarinemaster #mm300 #seikowillard #naomiuemura #seikodiver #prospex #seikofam #watchcollector
Seiko 62MAS ref. SBDX019 with automatic caliber 8L Seiko 62MAS ref. SBDX019 with automatic caliber 8L35. The first re-creation of the 62MAS, from 2017. Mr. Gethin Christian’s review made me appreciate even more some of the finer details of this watch, which is truly stunning in person, especially the dial. Check his channel and also @mr_seikosha on Instagram! #seiko #62mas #seikodiver #seiko62mas #prospex #seikoholic #watchaddict #watches
Seiko Presmatic Hi-beat #vintageseiko #seikowatch Seiko Presmatic Hi-beat #vintageseiko #seikowatch #seiko #presmatic #seikomatic #watches #seikocollector
Seiko 5 Sports #seiko5sports #seikofive #seiko5 # Seiko 5 Sports #seiko5sports #seikofive #seiko5 #seikowatches #seiko #watches #vintageseiko #mechanicalwatch #watchesofinstagram
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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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