Patek Philippe 3940: Reference Guide

The Patek Philippe reference 2551, often referred to as the "Disco Volante" due to its distinctive case profile, represents a significant design departure for the brand in the mid-20th century. This reference is characterized by its broad, flat bezel and integrated lugs, creating a sleek and modern aesthetic that was forward-thinking for its era. It is recognized for its clean dial layouts, typically featuring applied hour markers and a small seconds sub-dial, emphasizing legibility and understated sophistication. The reference 2551 was produced in various precious metals, with subtle variations in dial and case execution across its production run.

Crafted in 18k yellow gold, the case of the reference 2551 measures 35 mm in diameter. It houses the Patek Philippe caliber 10-200, a manual-winding movement known for its reliability and slim profile, which contributes to the watch's elegant wearability. The watch is fitted with a sapphire crystal, providing clarity and scratch resistance. While water resistance is rated at 30m, it is primarily intended for protection against incidental moisture. The smooth bezel design further accentuates the watch's clean lines.

This reference appeals to collectors seeking Patek Philippe's mid-century design innovation, particularly those drawn to its unique case architecture. Variants in white gold (2551G) and rose gold (2551R) exist, with the G models noted for their smaller production quantities and distinct index and small second designs compared to the R models. The reference 2551 offers a blend of classic Patek Philippe craftsmanship with a distinctive design that sets it apart from more traditional round dress watches of the period.

The Patek Philippe Reference 3940 is a perpetual calendar wristwatch that was introduced in 1985, succeeding the Reference 3450. It is notable for its relatively slim profile and the integration of a perpetual calendar complication in a refined case. This reference became a cornerstone of Patek Philippe's complicated watch offerings for nearly two decades, establishing a design language for subsequent perpetual calendar models. It represents a significant period in the brand's modern history of complicated timepieces.

The watch features a 36mm case, typically crafted from yellow gold, rose gold, white gold, or platinum. It houses the self-winding Caliber 240 Q movement, which is known for its micro-rotor construction, contributing to the movement's thinness and allowing for a slimmer case profile. The movement provides a power reserve of approximately 48 hours. The dial is protected by a sapphire crystal, often accompanied by an interchangeable solid case back and a sapphire display back.

Reference 3940 is highly regarded by collectors for its classic proportions and the enduring appeal of its perpetual calendar display, which includes day, date, month, leap year cycle, and moon phases. It was produced in several series, with subtle variations in dial layout and typography, making early series examples particularly sought after. The reference is considered a benchmark for perpetual calendar watches and remains a significant piece for those appreciating traditional horological complications.