The watch demanded the best in Swiss engineering and British craft. The complication module was created exclusively for Bremont by Agenhor in Geneva, masters of ingenious mechanics.

Founded in 1996 by horological visionary Jean-Marc Wiederrecht and now led by his sons, Laurent and Nicolas, Agenhor has earned numerous accolades for its groundbreaking innovations, featured in timepieces from esteemed brands such as MB&F, H. Moser & Cie, and Hermès.

At the heart of the Altitude Perpetual Calendar lies a complication that showcases Agenhor’s mastery. The movement encompasses a unique perpetual calendar complication with a second time zone displayed by a disc and with mono-pusher functionality.

The rotating disc positioned at 12 o’clock offers intuitive at a glance readability of a second time zone, which can be adjusted effortlessly via the crown’s mono-pusher function — a thoughtful feature designed with frequent travellers in mind. The movement’s architecture is elevated further by exquisite finishing, including Côtes de Genève decoration across the module’s bridges and a beautifully skeletonised Wayfinder logo on the lever of the mono-pusher.

The base calibre is a manually wound movement from Sellita, the AMT6900. This is crafted within Sellita’s top-tier, custom-build AMT (Atelier Manufacture Technique) programme.

The combined movement measures just 6.8mm — keeping the case a lean 12.65mm.

For Bremont’s design team, the challenge was to build a perpetual calendar that still looked and behaved like a pilot’s watch. Most perpetual calendars are delicate dress pieces — admired, but rarely tested. Bremont’s mission is to craft the finest timepieces for Air, Land and Sea, mixing modern British elegance with durability, and style.

As CEO Davide Cerrato explains:

“The combination of a perpetual calendar and GMT function is extremely rare in watchmaking, but for Bremont it gives us the perfect mix of classical sophistication and adventurousness. It had to be as robust as any Altitude watch, easy to use, and durable. It’s intended as an everyday watch, not a delicate item that lives in the safe.”

The solution was clear: a display built for legibility. Hours, minutes, and running seconds are set out with purpose. At 12 o’clock, a rotating globe tracks home time on a 24-hour ring. At 6, a pointer marks the date and at 3, a propeller hand advances the months and leap years in 172 steps across a four-year cycle.

AERIAL ELEGANCE

The Altitude Perpetual GMT combines innovative functionality with true elegance, following the aviation-inspired design codes of the Altitude Collection. Every detail reflects the Altitude DNA — from the subtle propeller hands to the Air Force Blue dial and barrel, recalling the colours of RAF uniform.

The 42mm case and bracelet, crafted from lightweight Grade 2 titanium, showcase the collection’s signature three-piece Trip-Tick case construction. Thanks to its precision engineering, the watch delivers the unwavering performance expected of a complex timepiece built to endure for decades – if not centuries.

Each of the 50 limited edition pieces is hand-assembled at The Wing in Henley-on-Thames, Bremont’s home of British watchmaking — and the only end-to-end watch manufacture on these shores.

The perpetual calendar is one of watchmaking’s greatest innovations — a mechanism that automatically knows the length of every month and leap year, with no adjustment needed until the year 2100. Its origins lie in Britain, where Thomas Mudge — best known for inventing the lever escapement — the backbone of almost every mechanical watch since — built the first perpetual calendar in 1762.

By ‘remembering’ the four-year cycle of 1,461 days, the mechanism adjusts for 30- and 31-day months, and for February’s 28 or 29 days. More than two centuries later, it remains one of watchmaking’s most respected complications.