Seiko 7S26 / NH23 Movement Parts

The NH23 and the 7S26 movements are quite similar because they are both simple, reliable automatic movements produced by Seiko Instruments Inc. (SII). However, the NH23 is a more modern version designed for external manufacturers (e.g., microbrands), while the 7S26 was exclusively used in Seiko watches. Here are the key differences and similarities:

Similarities

Mechanical Base:
- Both are automatic movements without manual winding or hacking features.
- They share similar specifications:
  - Beats per hour (BPH): 21,600.
  - Power reserve: Approximately 40 hours.
  - Number of jewels: 21.
Use Case:
- Both are designed for entry-level, affordable watches.
- Renowned for their simplicity, reliability, and low maintenance.
Day and Date Complication:
- Both movements feature a day-date function, often with the day displayed in two languages (depending on the watch).

Differences

Feature	NH23	7S26
Purpose	Designed for external manufacturers (microbrands, aftermarket).	Exclusive to Seiko watches.
Production	Modern version, still in production.	Discontinued, no longer produced.
Calibration	Basic settings, often adjusted by the manufacturer.	Pre-calibrated by Seiko for their watches.
Parts Availability	Easily available in aftermarket.	Harder to find due to discontinued status.
Rotor Branding	Unbranded or marked with "SII".	Seiko-branded.
Compatibility	Compatible with a wide range of watch cases.	Specific to Seiko watch cases.

Advantages of the NH23 Over the 7S26

Availability:
- The NH23 is still in production and readily available from aftermarket and wholesale channels.
- The 7S26 has been discontinued, making it harder to source complete movements or spare parts.
Flexibility:
- The NH23 is widely used by microbrands and external manufacturers, offering greater versatility.
- The 7S26 was limited to Seiko watches, making it less adaptable for aftermarket use.
Modernized Production:
- While functionally similar, the NH23 benefits from more modern production techniques, potentially offering improved consistency and reliability.

When to Choose Which?

NH23:
- Best for new watches, microbrand projects, or aftermarket replacements.
- Ideal when you need a modern, widely available movement.
7S26:
- Only relevant for repairing Seiko watches or vintage projects where using an original Seiko movement is essential.

Conclusion

The NH23 is essentially a modern, aftermarket-oriented version of the 7S26. The primary difference lies in availability and target audience: the NH23 is versatile and designed for broader applications, while the 7S26 is a classic Seiko movement that was exclusive to Seiko watches.

Crown and sten

Perfect fit and works as it should. Thanks

Good!

original part for a very good price. part was temporarily unavailable, but was later delivered with good communication by email. I recommend this site.

Dear valued customer,

Thank you for your review! We are glad to hear that you had a good experience with our product and our customer service. We apologize for the delay in availability but we are happy to know that it was resolved with good communication. Thank you for recommending our site and we hope to serve you again in the future.

Best, Team Watch-Plaza

I was thrilled to find that Watch Plaza had a genuine Seiko replacement part for my SBDC003. This is a first generation Sumo and it is difficult to find OEM parts. The price was fair and shipping went very smoothly. Thank you Watch Plaza!!

Hi there, thank you for your kind review! We're happy to hear that you were able to find a genuine replacement part for your SBDC003 at Watch Plaza. We understand how difficult it can be to find OEM parts for first generation models. We strive to offer fair prices and smooth shipping for all our customers. Thank you for choosing Watch Plaza!

Cinturino diesel

Il cinturino è arrivato subito . Tutto ok ! E perfetto anche imballaggio, tutto ok

Perfect

Ik heb een seiko 5 horlogebandje gekocht.
Het nieuwe bandje monteren ging wel goed.
Levertijd binnen een week.

Hi there,
Thank you for your review! We are happy to hear that the new Seiko 5 watch band was a perfect fit for your watch and that the installation process went smoothly. We strive to provide top-quality products and fast delivery, so we are glad we could meet your expectations. Thank you for choosing our brand and we hope you enjoy your new watch band. Have a great day!

Seiko 7S26 / NH23 Parts