The CHRONOMASTER Open offers a view of the beating heart of the El Primero movement from the dial. Crafted in a sleek 39.5mm steel case, this version features a matte silver dial with tricolour counters and a transparent counter for the running seconds, paired with an integrated steel bracelet. Powered by the El Primero 3604 1/10th of a second automatic chronograph movement.

Movement
Movement: El Primero
Components: 269
Frequency: 36,000 VpH (5 Hz)
Power reserve: approx. 60 hours

Functions
Hours and minutes in the centre
Small seconds at 9 o'clock
1/10th of a second Chronograph:
- Central chronograph hand that makes one turn in 10 seconds
- 60-minute counter at 6 o'clock
- 60-second counter at 3 o'clock

Case
Material: Stainless steel
Diameter: 39.50
Water resistance: 10 ATM
Dial: Silver matte with two different-coloured counters & an Hesalite counter

Strap
Strap: Metal bracelet

Reference
03.3300.3604/69.M3300