Brand-new, New Old Stock (NOS) Seiko 4R35 automatic mechanical movement.
This iconic hacking and hand-winding workhorse is unused and working well
This specific 4R35B caliber features the premium Black Date Disc configuration, engineered specifically to align seamlessly behind dark, stealth, sunburst, or PVD-coated dials without ruining the symmetry of the watch face.
Crucially, this is a genuine branded Seiko production unit featuring the clean factory rotor layout, making it the mandatory component required for watch models utilizing an exhibition sapphire or hardlex caseback.
Do not downgrade a premium timepiece with an unbranded trade blank; this original component preserves the full authenticity and market value of the watch
Running at 21,600 vibrations per hour (vph / 3Hz), the Calibre 4R35 is highly celebrated for its extreme durability and daily reliability.
- Central 3-hand tracking (Hours, Minutes, and hacking sweeping second hand)
- Advanced Diashock shock-protection system protecting the balance assembly
- Bi-directional automatic winding via Seiko’s high-efficiency system, plus integrated auxiliary manual crown-winding
- Precision calendar quick-set function
- Robust 41-hour static power reserve
While the 4R35 platform is remarkably tough, watches worn daily or taken deep into marine environments inevitably experience seal degradation. Moisture intrusion rapidly oxidizes the hairspring, tarnishes the mainspring train, or rusts winding pivots. Additionally, old or dirty lubrication lines drag down amplitude.
The movement is unused, in excellent working order
Comes with the factory stem, as well as a new uncut winding stem
Technical Note for Watchmakers:
As this is genuine New Old Stock, it comes equipped with the temporary plastic shipping stem. When installing into its final case, remove the shipping stem and trim / fit your new stem. Ensure proper dial-foot alignment before seating to avoid binding the calendar wheel
We have other genuine Seiko watch movements for sale
Posted quickly and packaged safely