Launched in 2020, the Overseas Perpetual Calendar Ultra-Thin by Vacheron Constantin showcases a refined design with its elegant 41.5 mm case and integrated bracelet crafted from 18K 5N pink gold. This luxurious timepiece features a striking blue lacquered dial accented by a satin-finished center and a velvet-textured outer minute track, elegantly displaying the day, date, month, and leap year, as well as a moon phase indication. The moon phase is artfully represented with two 18K gold moons set against a vivid starry blue backdrop, complemented by applied 18K gold hour markers and luminescent hour and minute hands enhanced with blue Super-LumiNova.

Housed within the case—measuring 8.1 mm in thickness—this watch offers magnetic protection, is water-resistant up to 50 meters, and features a transparent sapphire crystal case back. It is powered by the Vacheron Constantin calibre 1120 QP, an ultra-thin automatic perpetual calendar movement that is just 4.05 mm thick and operates at a frequency of 19,800 vibrations per hour, providing roughly 40 hours of reserve power. Notably, this perpetual calendar is designed to accommodate varying month lengths and leap years without needing adjustment until 2100. Additionally, the reference 4300V/220R-B509 is not only available with a beautifully crafted 18K 5N pink gold bracelet, but it also includes interchangeable dark blue grained calfskin leather and rubber straps, complete with an 18K 5N pink-gold pin buckle. This exquisite timepiece is also certified with the Geneva Seal.