Patek Philippe TechNews #5: Alarm Travel Time Ref. 5520 - Section 3

With the detailed explanations and technical animations of the Patek Philippe TechNews video, you can discover the alarm mechanism of the self-winding Ref. 5520 Alarm Travel Time grand complication. Learn more about programming the 24-hour alarm, the systems that protect the movement against damage in the event of incorrect manipulation, and the hammer that strikes a classic fine-tuned gong. The sound quality is worthy of a minute repeater.