Seiko SII caliber NH38A Drawings

Seiko (SII) Caliber NH38A

Seiko SII caliber NH38A Drawings

ManufacturerSeiko (SII, TMI)
Caliber NumberNH38A
Movement TypeAutomatic
Jewels24
Vibrations Per Hour
21,600 bph
Shock System?Yes
Power Reserve
41 hours
Winding Direction
Bi-directional
Hacking?Yes
Diameter27.40mm (outside) / 29.36mm (casing)
Height5.32mm
FunctionsHours, minutes, central seconds
Country of ManufactureJapan/Malaysia
Known Brands
Invicta (add more in the comments below)

keepthetime-468-60

 

 

The Seiko caliber NH38A is very similar to the popular caliber NH35A.The NH38 series is often found with an open balance wheel at 9:00 on the dial.

Time Module (TMI) claims an accuracy rating of -20~+40 seconds per day.

What is the difference?

Unlike the NH35A, the NH38A is a basic three hand watch and does not have a day or date complication.

Japan or Malaysia?

The complete Japanese-made caliber number is NH38A3J. For the Malaysia variant, the number is NH38A3M.

The large photo below is of a Seiko NH38A movement in an Invicta 22744 watch.

 

Seiko SII caliber NH38A in an Invicta watch

Submitted by Nathaniel B.

You are reading Caliber Corner, the most popular resource for watch movement pics, specs and opinions, including mods and DIY repairs. CC is a watch geek community for gear turning and caliber learning! Check the front page for the latest caliber listings and follow Caliber Corner on Twitter, Instagram and Facebook. Subscribe to our YouTube channel for close-up movement videos. Join our mission to spread movement awareness. Sign up!
What do you think about Seiko (SII) Caliber NH38A? Keep comments respectful and follow our community guidelines.
Subscribe
Notify of
guest
24 Comments
oldest
newest most voted
Inline Feedbacks
View all comments
Tracey Deel
Tracey Deel
3 years ago

I have this movement in an ARAGON, was Android by Wing Liang.

Jürgen Albers
Jürgen Albers
3 years ago
Doug
Doug
3 years ago

Helm Khuraburi uses the nh38a

Paul Overby
Paul Overby
2 months ago
Reply to  Doug

I have the Helm Khuraburi. So far, I am experiencing around +5 second per day with the NH38.

Joris
Joris
3 years ago
Zoroff
Zoroff
2 years ago

Armourlite also uses NH38

Will
Will
2 years ago

I have this watch in a Momentum Morioka watch.

Bert
Bert
2 years ago
Reply to  Charles Laigo

My Phoibos Wavemaster is a great watch but the Seiko movement in it is at least 10 seconds a day slow, a common issue. I wish brands would regulate these movements before shipping!

Rich
Rich
2 years ago

My Giorgio Fedon has this movement.

W
W
2 years ago

Traska Freediver

Øyvind
Øyvind
1 year ago

Used by Giorgi Fedon 1919

Roger Ingram
Roger Ingram
1 year ago

Also found in Traska watches

Jeff Summers
Jeff Summers
2 months ago
Reply to  Roger Ingram

Hey I am a huge fan of yours. Had one of your Jupiter trumpets for years. You should check out my YouTube channel at https://www.youtube.com/channel/UCnGYxMEr5niyVeTjduwLBpw
Awesome you are a watch fan too!!

Best,
Jeff Sumners

koimaster
koimaster
1 year ago

I love coming to this site to learn more about movements and to share.

Rudy
Rudy
1 year ago

There is a typo in the table box.
Malaysia not Maylasia. 🙂

Remco
Remco
10 months ago

This movement is also used in the limited edition TW Steel’s Son of Time MST6.

evansna
evansna
3 months ago

Aquacy Cave Diver uses as well

trackback
Vario Empire Tuxedo – White & Gold – Beans & Bezels
2 months ago

[…] doesn’t work for you, you can also look at the automatic variant of this model that houses a Seiko NH38A. This comes at the cost of an additional 0.5mm of case thickness. In my opinion, the hand-wound […]

GreyMisha
GreyMisha
1 month ago

My invicta Master of the oceans uses this Caliber too. Very useful webpage. Thanks

Chris
Chris
1 month ago

In Zum watch R1
(In kikstarter actually)

justin hanson
justin hanson
27 days ago

vario is also using this movement

24
0
Would love your thoughts, please comment.x
()
x