Introduction: Why Seiko’s NH Series Matters

In the world of horology, movements are the beating heart of every timepiece. Among the myriad of mechanical movements available today, the NH series—manufactured by Seiko Instruments Inc. (SII)—has carved out a unique position as one of the most reliable, affordable, and widely used automatic movements in the industry. The NH series, especially the NH35, NH36, and their derivatives, have revolutionized the microbrand watch industry and have played a crucial role in making automatic watches accessible to a wider audience.

Whether you are an avid watch enthusiast, an aspiring collector, or an independent watchmaker, understanding the significance of the NH series movements is essential. This article will dive deep into the history, specifications, advantages, and impact of these movements on the horology landscape.

The Origins of the NH Series

The NH series is essentially a rebranded version of Seiko’s legendary 4R series movements, with slight modifications for third-party manufacturers. Seiko, a pioneer in watchmaking, introduced the NH series to cater to brands outside of its own portfolio, offering a robust and reliable movement that could be utilized in affordable automatic watches without compromising quality.

The Link to the Seiko 7S26

Before the NH series, Seiko’s 7S26 movement was a benchmark for affordable automatic movements, found in legendary models like the Seiko SKX007. The NH series builds upon this legacy with additional functionality and enhancements, making it a go-to choice for watchmakers worldwide.

Key Movements in the NH Series

1. NH35A – The Workhorse of the Industry

The NH35A is by far the most famous movement in the NH series and is often compared to the ETA 2824-2 and Miyota 8215 in terms of reliability and popularity.

Specifications:

• Type: Automatic, Hand-Winding, Hacking
• Jewels: 24
• Vibrations: 21,600 beats per hour (6 ticks per second)
• Power Reserve: ~41 hours
• Accuracy: -20/+40 seconds per day
• Complications: Date function

Why It Stands Out:

• Offers hacking seconds, a feature absent in its predecessor (7S26)
• Allows for manual winding, improving convenience for users
• Easy to regulate, making it a favorite among modders and watchmakers
• Affordable yet reliable, providing excellent value for money

2. NH36A – The Day-Date Companion

The NH36A is almost identical to the NH35A but comes with an additional day complication, making it a direct replacement for the Seiko 4R36 movement.

Specifications:

• Same as NH35A with the addition of a day display

Popular Use Cases:

• Found in watches that require a day-date function, such as Seiko 5 Sports models
• Preferred by microbrands producing tool watches with added functionality

3. NH38A/NH39A – No-Date Variants

For watchmakers who want a cleaner dial layout, the NH38A and NH39A offer no-date movements with an open-heart feature on some models.

Best For:

• Dress watches with a minimalist aesthetic
• Skeletonized watches showcasing the movement

4. NH70/NH71 – Skeletonized Versions

These movements are built for open-dial watches, providing an unobstructed view of the inner workings while maintaining the reliability of the NH series.

Why Watchmakers Love Them:

• Adds a luxury appeal to budget-friendly watches
• Allows brands to experiment with unique designs

The Impact of NH Series on the Watch Industry

1. Revolutionizing the Microbrand Market

Before the NH series became widely available, microbrands often had limited choices for automatic movements. The NH35 and NH36 opened the floodgates for affordable, high-quality automatic watches, enabling independent brands to thrive without sourcing high-cost Swiss movements.

2. Customization and Watch Modding

One of the biggest reasons for the NH series’ popularity is its adaptability. Enthusiasts and modders worldwide favor the NH35 for custom watch builds due to its ease of regulation, availability of spare parts, and compatibility with a vast range of cases and dials.

3. Affordability Without Sacrificing Quality

While Swiss movements like the ETA 2824-2 and Sellita SW200 dominate the luxury sector, the NH series offers an economical alternative with nearly comparable reliability. This has enabled budget-conscious consumers to experience true mechanical watchmaking without breaking the bank.

4. Durability and Reliability

NH movements are designed for rugged use, with shock resistance and long-lasting durability. Unlike Miyota movements, which can exhibit rotor wobble, the NH35 and NH36 maintain smooth operation even under demanding conditions.

Comparing NH Series to Competitor Movements

The Future of the NH Series

As the demand for affordable automatic watches grows, the NH series will likely continue evolving. Potential advancements may include higher beat rates, improved power reserves, and enhanced accuracy. Seiko’s commitment to innovation ensures that the NH series will remain relevant for years to come.

Conclusion: Why the NH Series Remains King of Affordable Automatics

The NH series has democratized automatic watches, providing a balance of affordability, reliability, and customization potential. Whether you are a watch collector, microbrand entrepreneur, or modding enthusiast, the NH35, NH36, and their counterparts offer an unparalleled value proposition.

With its blend of Japanese craftsmanship, robust performance, and versatility, the NH series continues to shape the watch industry, proving that quality timekeeping doesn’t have to come with a hefty price tag.