Calibre Springs Hours: Understanding the Seiko NH35A Movement

The Seiko NH35A movement is one of the most popular automatic movements in the world, widely used in many affordable and microbrand watches. But what makes it so special? In this article, we'll dive into the details of the NH35A movement and explore its features, accuracy, and compatibility with various watch brands.

Accuracy and Technical Details

According to Time Module's technical documentation, the Seiko NH35A movement has an accuracy range of -20~+40 seconds per day under normal conditions. This means that the movement can deviate from its actual time by up to 80 seconds daily. However, this shouldn't have any noticeable bearing on the watch's overall performance.

History and Evolution

The Seiko NH35A movement is essentially an unbranded version of the Seiko caliber 4R35. The earliest documentation we could find was issued in 'date', which corresponds to the 2011-2012 time frame when the first NH35A-powered watches started hitting the market.

The NH35A movement is a hand-windable, hacking upgrade from the Seiko caliber NH25A. It features central hours, central minutes, and central sweeping seconds, with a date calendar at 3:00 (sometimes located in other positions depending on the dial design). This movement is widely available and has been used by various brands such as Invicta, Vostok, Lum-Tec, Spinnaker, Minus-8 Layer, Advisor AstroHelm, and many others.

In conclusion, the Seiko NH35A movement is a reliable and popular automatic movement that offers excellent accuracy and durability. Its compatibility with various watch brands makes it an attractive option for those looking for affordable and high-quality timepieces. Whether you're a watch enthusiast or just starting your horological journey, understanding the Seiko NH35A movement can help you appreciate the craftsmanship and innovation that goes into creating these precision timekeeping devices.

Calibre springs hours