In 2010, Dutch watchmakers Tim and Bart Grönefeld presented “One Hertz”, the world’s first and only production wristwatch with independent dead seconds. Its first edition, the “One Hertz 1912” was consisted of 12 limited edition timepieces featuring stainless steel case.
Following the success of One Hertz 1912 edition, Grönefeld presents “One Hertz Dune” red gold in a limited edition of 20 pieces.
The One Hertz features Grönefeld’s own proprietary movement and indicates hours and minutes on a sub-dial at 2 o’clock; large sub-dial for the dead seconds; power reserve indicator at 12 o’clock; and an innovative setting-winding indicator at 3 o’clock. Setting-winding is ergonomically selected by pushing the crown in rather than pulling it out.
Model: Grönefeld “One Hertz Dune” red gold
Edition : Limited edition of 20 pieces
Calibre: G-02, mechanical hand winding, independent dead seconds, power reserve Indicator and setting indicator.
Movement dimensions: 35mm x 9.4 mm
No. of parts: 285 parts
No. of jewels: 39 jewels set in gold chatons
Power reserve: 72 hours
Barrels: 2 barrels, one for the going gear train and one for the independent dead seconds mechanism. Both Barrels are wound at the same speed and in the same direction
Balance wheel: 9.12 mm free sprung variable inertia balance wheel
Balance frequency: 21’600 bph/ 3 Hz
Balance spring: Phillips terminal overcoil curve, triangle-style stud
Main Plate: Spotted rhodium plated nickel silver
Bridges: Stainless steel hand bevelled, micro-blasted, circular grain on the top, relief engraved on micro blasted surface
Gearing: two independent gear trains each with their own energy source
Dead seconds mechanism: independent mechanism, cam with 30 teeth on the going gear train on the second’s wheel, escape wheel on the seconds wheel of the independent gear train, double lever with jewelled pallets.
18ct 5N rose gold, limited edition of 20 pieces, gold security screws
Polished bezel and centre band with hand-finished straight graining.
Case dimensions: 43 mm x 12.5 mm
Sapphire crystals: top domed with anti-reflective treatment both sides
Display back with anti-reflective treatment inside.
Water resistance: 3atm/30m/100 feet.
Crown: Rose gold with engraved “G” logo
Hour and minutes subdial, raised seconds sapphire subdial (transparent over the hour and minute subdial), power reserve indicator, setting-winding indicator, Grönefeld logo and model name on individual screwed down nameplates
Hands: Hours and minutes, long thin counter-poised seconds, power-reserve and setting-winding.
Strap and buckle
Hand-sewn matte black, alligator leather with rose gold engraved tang buckle to match case.