La Joux-Perret L121

The L121 is an automatic chronograph movement manufactured by La Joux-Perret. It measures 30.4mm in diameter and 7.9mm thick, operates at 4 Hz (28,800 vph), and delivers a 60-hour power reserve. The movement features a GMT 24h complication with center chronograph seconds, a 30-minute counter at 12h, a 12-hour counter at 6h, and small seconds at 9h. It contains 26 jewels in automatic configuration (24 in manual) and includes a unidirectional winding rotor with optional hand winding and hacking seconds.