The CHRONOMASTER Open offers a view of the beating heart of the El Primero movement from the dial. Crafted in a sleek 40mm 18K rose gold case, this version features a matte silver dial with tricolour counters and a transparent counter for the running seconds, paired with a blue calfskin leather strap. Powered by the El Primero 3604 1/10th of a second automatic chronograph movement.