The Seiko NH35 is a Japanese automatic movement manufactured by Seiko Instruments Inc. (SII) and widely used across the watch industry in both genuine mid-range watches and replica references. It is a 24-jewel movement running at 21,600 bph (6 beats per second), offering a power reserve of approximately 41 hours, and includes both hacking and hand-winding functionality. The NH35 is derived from the Seiko 4R35 calibre and shares its fundamental architecture with the NH36, which adds a day display. Its combination of reliable performance, reasonable accuracy, and broad availability has made it one of the most commonly specified movements in the mid-tier replica watch segment.
In replica watches, the NH35 is used in references where a dependable Japanese automatic movement is preferred over a Chinese-manufactured calibre. Its 21,600 bph beat rate produces a clearly stepped seconds hand — 6 ticks per second — rather than the smoother sweep of 28,800 bph movements. The NH35's timekeeping accuracy under normal conditions is typically within −10 to +30 seconds per day, consistent with other movements in its class. The movement is relatively straightforward to service and has a well-documented architecture, which means repair and regulation are accessible to watchmakers familiar with Seiko calibres. Its exhibition caseback appearance — a clean, functional rotor and bridge layout — is recognisable and well-regarded among buyers who evaluate movement finishing quality.
In Practice
- The NH35 runs at 21,600 bph, producing a seconds hand that advances in 6 distinct steps per second. Buyers who prefer a smoother seconds hand motion should look for replica references specified with 28,800 bph movements such as the Miyota 9015 clone or higher-grade ETA clone calibres. The stepped motion of the NH35 is normal and correct — it is not a defect.
- The NH35 includes both hacking and hand-winding, which are positive quality indicators for a movement in this class. Hacking allows precise time synchronisation by stopping the seconds hand when the crown is pulled out. Hand-winding allows the mainspring to be wound manually when the watch has not been worn — useful when starting the watch after storage.
- The NH35 is a three-hand movement with date only — it does not include a day display. The NH36, a closely related calibre, adds a day wheel. Buyers evaluating replica references should verify whether the specification lists NH35 or NH36 when the reference includes both day and date displays, as the two movements are not interchangeable without dial modification.
- The NH35 is a genuine Seiko-manufactured movement, not a clone. In replica watches it is used as an original calibre — the same movement Seiko supplies to its own watch brands. This distinguishes it from ETA clones and Chinese-manufactured calibres. Its genuine origin contributes to its reliability and serviceability reputation in the replica market.
- Power reserve of approximately 41 hours means the NH35 will run for roughly one and a half days after being removed from the wrist. Regular daily wear of 8 or more hours is sufficient to maintain full wind under normal activity levels. The movement can be hand-wound to full reserve in approximately 20–25 crown rotations from a fully depleted state.
Related Terms
Automatic Movement · Miyota Movement · Hacking · Beats Per Hour · Power Reserve
Read Next
For a full comparison of automatic movement types used in replica watches — including NH35, Miyota, and clone calibres — read: Replica Watch Movements Explained