MB&F

The Legacy Machine Perpetual, launched in 2015, is based on a new type of perpetual calendar developed for MB&F by independent watchmaker Stephen McDonnell. Unlike the traditional perpetual calendar, which calculates the length of the months based on the length of the longest month – 31 days – McDonnell’s perpetual calendar takes the length of the shortest month of 28 days as the base duration. The change in concept was to make the calendar more user-friendly and included a leap year corrector, which does not exist in traditional perpetual calendars. In addition, the McDonnell system includes protection of the calendar against breakage. It can prevent problems if a correction attempt is made at the same time as the calendar displays change. This makes the LM Perpetual movement very complicated. Normally, a perpetual calendar caliber consists of about 200 parts (Patek Philippe’s caliber 240 Q, one of the best in this category, has 275 parts, for example), while McDonnell’s perpetual calendar is composed of 581 parts. This is not only proof of the great complexity of the calendar mechanism, but also the reason for the high value of Legacy Machine Perpetual watches and their focus primarily on collectors and connoisseurs of fine watchmaking. For the same reason, the edition of almost all versions of the Legacy Machine Perpetual is limited. The design of the Legacy Machine Perpetual is a continuation of the style of all previous MB&F Legacy Machine releases – with a round case, a high-domed sapphire crystal and a balance and hairspring mounted in the center of the dial under an arched bridge (a so-called "floating balance"). In 2015, MB&F launched the Legacy Machine Perpetual with two limited editions in 18k rose gold (this watch; grey movement mainplate) and 950 platinum (blue movement mainplate), each with 25 pieces. Further variants were offered in the following years, including two 2017 models in white gold with purple movement mainplate (25 pieces) and with grey movement mainplate (unlimited production); 2020 model in 18k yellow gold with blue movement mainplate (25 pieces); three 2020 limited editions of the LM Perpetual EVO Zirconium with 15 pieces each and different movement mainplate colors (grey, orange and blue); 2021 LM Perpetual Evo in titanium with green movement mainplate (50 pieces); LM Perpetual Palladium with aquamarine-colored movement mainplate (2021; 25 pieces); 2023 LM Perpetual Stainless Steel with salmon-colored movement mainplate (unlimited production); 2024 LM Perpetual Evo in titanium with ice blue movement mainplate (unlimited production). To celebrate the opening of the MB&F LAB in Silicon Valley in 2024, the series was complemented by the LM Perpetual Evo Silicon Valley in rose gold with ocean blue movement mainplate (18 pieces). Finally, in 2025, MB&F presented the anniversary edition LM Perpetual Longhorn in stainless steel with a rhodium-plated movement mainplate to celebrate the 20th anniversary of the brand (20 pieces).

This Legacy Machine Perpetual Rose Gold Limited Edition 25 by Stephen McDonnell is definitely one of the highlights of the MB&F collection due to its unique design, the excellent and elaborate hand finishing of the case, dial and both sides of the movement, as well as the unique perpetual calendar mechanism invented for MB&F by independent watchmaker Stephen McDonnell. The focus of this watch is on the openworked dial, which reveals the stunningly complex and therefore particularly attractive calendar mechanism that can only be found in the MB&F LM Perpetual watch. What makes this watch even more attractive is the fact that it is an inaugural edition in rose gold and is rare, as only 25 pieces were produced.