SEIKO (SII) NH35/NH36/NH37/NH38/NH39 Second Reduction Wheel #0514183

Product Description

The SEIKO (SII) NH35/NH36/NH37/NH38/NH39 Second Reduction Wheel (#0514183) is a genuine Japanese-made component for the popular NH series automatic movements. As part of the gear train, the second reduction wheel works within the power transmission system to ensure stable and accurate timekeeping . This brand new original part is essential for watchmakers restoring proper movement function when the original component becomes worn or damaged.

Features & Function

• Genuine Seiko/SII part – authentic Japanese-made component for NH35, NH36, NH37, NH38, and NH39 movements

• Gear train component – works within the power transmission system for accurate timekeeping

• NH family compatibility – compatible across the most popular NH series calibers 

• Direct replacement – drop-in replacement for worn or damaged second reduction wheels

Specifications

• Part Number: 0514183

• Compatible Movements: Seiko NH35, NH36, NH37, NH38, NH39 (also known as 4R35/36/37/38/39)

• Movement Family: NH Series (Basic Mechanical Series) 

• Movement Frequency: 21,600 vph (3 Hz)

• Jewels: 24

• Power Reserve: >41 hours

• Hacking: Yes (seconds hand stops when crown pulled to position 2)

• Hand-Winding: Yes

• Winding Direction: Bi-directional

• Origin: Japan

Applications

• Service and overhaul – replacing worn or damaged second reduction wheels in NH series movements

• Gear train restoration – ensuring stable power transmission for accurate timekeeping

• Suitable for professional watchmakers and experienced repair technicians

FAQs

1. Is this a genuine Seiko/SII part?

Yes, this is a genuine Seiko (SII/TMI) factory part made in Japan. The NH series is manufactured by Seiko Instruments Inc. (SII) and distributed by Time Module Inc. (TMI). The NH prefix indicates it is sold without Seiko branding for use by third-party watch manufacturers and the mod community .

2. Which movements is this second reduction wheel compatible with?

This second reduction wheel is compatible with Seiko NH35, NH36, NH37, NH38, and NH39 movements. These are all based on the same NH35 architecture, with differences in complications (date/day-date/24-hour/open heart) . The gear train components are shared across these calibers.

3. What are the signs that the second reduction wheel needs replacement?

Common signs include irregular timekeeping, low amplitude, or visible wear/damage to the teeth or pinion during movement inspection. A qualified watchmaker can diagnose these issues during servicing.

Why Choose SOFLY Watch Parts?

• Fast worldwide shipping within 3 business days.

• Competitive pricing on Seiko/Hattori calibers.

• 3,000+ watch movements and parts in stock.

• Trusted by watchmakers worldwide.

• Personalized sourcing support via [email protected] or WhatsApp +86 18620212114.