The Bremont Terra Nova Jumping Hour introduces a new technical direction for the Terra Nova field watch collection, marking the first integration of a Jumping Hour complication within the brand’s offerings. Developed in collaboration with Sellita, the new calibre BC634 is exclusive to Bremont for two years and represents a focused approach to mechanical innovation, while retaining the design language inspired by early 20th-century military pocket watches. The collection features two distinct models: a limited edition 38 mm version in cupro-aluminium bronze and a 40.5 mm version in 904L steel, each with its own interpretation of the Jumping Hour mechanism and the Terra Nova design ethos.
The 38 mm bronze edition adopts the ‘Montre à guichet’ style (5450€ bracelet / 5900€ bracelet), presenting three linear apertures for hours, minutes, and running seconds. The hour is displayed through a window at 12 o’clock, with brown printed numerals on both the hour and minute discs. The running seconds are indicated by a black hand visible through a dedicated window. Each of these apertures is protected by its own sapphire crystal, enhancing both durability and legibility. The closed-case design and the use of brown tones on the numerals contribute to the model’s distinctive appearance, while the overall layout is reminiscent of historic timekeeping instruments.
In contrast, the 40.5 mm steel edition (4200€ strap / 4500€ bracelet) features a black gloss dial with a more contemporary arrangement. The hour and minute windows are positioned to encourage a left-to-right reading flow, which aligns with the natural movement of the eye. The hour numeral is luminescent, and the dial incorporates triangular markers along with a full Super-LumiNova® sweeping seconds hand, ensuring high legibility in varying lighting conditions. This model preserves the cushion-shaped case and signature numerals characteristic of the Terra Nova line, while offering a more refined aesthetic.
Both models are powered by the Bremont Calibre BC634, developed in partnership with Sellita. This movement is equipped with 29 jewels, a Glucydur balance wheel, an Anachron balance spring, and a Nivaflex mainspring. It operates at a frequency of 28,800 vibrations per hour (4 Hz) and offers a 56-hour power reserve. The Jumping Hour mechanism itself functions through a system of gears and springs, enabling the hour disc to advance instantaneously at the completion of each hour. The high-torque configuration ensures that the jump occurs in less than one-tenth of a second, providing both precision and a visually dynamic time display.
The case of the 38 mm bronze edition is constructed from satin and polished cupro-aluminium bronze, chosen for its corrosion resistance and distinctive appearance. It features a two-piece design with a push-in crown and a decorated steel case back. The dimensions are 38 mm in diameter, 44 mm in length, and 20 mm lug width, with a water resistance rating of 3 ATM (30 metres). This version is limited to 100 pieces and is available with either a quick-release bronze bracelet or a brown leather strap with cream box stitching1.
The 40.5 mm steel edition utilises polished and brushed 904L stainless steel, a material known for its superior corrosion resistance and lustre. The case diameter is 40.5 mm, and it offers water resistance to 10 ATM (100 metres). This model is available with a 904L steel bracelet or a black leather strap, providing versatility in wear1.
The development and introduction of the Jumping Hour complication within the Terra Nova collection highlight Bremont’s technical capabilities in the field of mechanical watchmaking. The BC634 calibre’s high-torque, rapid-jump mechanism ensures accurate and reliable operation, and the exclusive partnership with Sellita for this movement underlines a strategic approach to innovation. By combining historically inspired design with a technically advanced movement, the Terra Nova Jumping Hour models represent a notable technical achievement within contemporary British watchmaking.
