Japan Genuine NH38 Automatic Movement Open Heart 24 Jewels High Accuracy
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Japan Genuine NH38 Automatic Movement Open Heart 24 Jewels High Accuracy
The Seiko NH38 Automatic Movement is a pure no-date automatic movement, designed for enthusiasts who appreciate dial symmetry and mechanical transparency. This 24-jewel caliber powers hours, minutes, and sweeping seconds with reliable precision. Featuring hand-winding and hacking capabilities, it operates at 21,600 vibrations per hour. Ideal for skeleton, open-heart, or minimalist builds, its clean dial-side architecture eliminates the "ghost" crown position found in date movements, offering uncluttered aesthetics and simplified operation .
Detailed Specifications:
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Movement Brand: Seiko Instruments Inc. (SII) / Time Module Inc. (TMI)
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Caliber Number: NH38A
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Type: Automatic, Mechanical
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Functions: Hours, Minutes, Sweeping Seconds (No Date/No Day)
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Jewels: 24
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Frequency: 21,600 A/h (3 Hz / 6 beats per second)
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Power Reserve: Approx. 41 Hours
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Winding: Automatic (Bi-directional "Magic Lever"), with Manual winding capability
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Hacking: Yes (Seconds hand stops for precise time-setting)
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Accuracy Rating: -20 ~ +40 seconds per day (23º± 2ºC)
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Regulation System: Triflat (standard regulator)
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Crown Positions: Position 0: Hand-winding; Position 1: Time-setting (hacking)
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Diameter: 27.4 mm (12 1/2 lignes)
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Height: 5.32 mm
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Shock Protection: Seiko Diashock system
| Color |
Silver |
|---|






