and an exclusive starter mechanism allow simultaneous resetting of the seconds as well as tenths and hundredths of a second.
e El Primero Caliber 9004 is Cosc-certified and has a 50hour power reserve for the time and a 50-minute power reserve for the chronograph. e 44-mm watch is available in three options: titanium (above right), priced at $9,600; titanium with an openworked dial (middle) for $10,600; and ceramicized aluminum with an openworked dial (above left) for $11,600.
— Zenith's new Defy El Primero 21, powered by the brand's new automatic Caliber El Primero 9004, has two escapements: one for time, beating at 36,000 vph (5Hz), and one for the chronograph, beating at a frequency of 50Hz, or 360,000 vph, allowing the chronograph to measure and display hundredths of a second on the central dial.
e new-generation twinbarrel El Primero 9004 has a balance spring made of carbonmatrix carbon nanotube composite, a Zenith-patented material that is resistant to gravity and temperature fluctuations according to Zenith. It is antimagnetic to 15,000 gauss. In addition to central hours and minutes, there is a small seconds sundial at 9 o’clock, a 1/100th-second central chronograph hand, a 30-minute totalizer at 3 o’clock, seconds and 1/10th second at 6 o’clock, and a percentage indication of the chronograph power-reserve at 12 o’clock. A patented chronograph-reset control mechanism composed of three heart pieces
Caliber El Primero 9004
Zenith Defy El Primero 21