The 1815 Up/Down draws on a patent obtained by A. Lange & Söhne in 1879 for a device that detects whether the movement is wound up or down. This was one of the brand's earliest patents and was used in several early pocket watches. When A. Lange & Söhne was relaunched in 1994, it was fitting that this power reserve system took a central place.

The 1815 Up/Down is powered by the caliber L942.1, which combines impressive technical and aesthetic features. The movement beats at a frequency of 3Hz, has a power reserve of 45 hours, and integrates a hacking seconds mechanism. The movement's aesthetics are just as impressive as its mechanics, with superbly hand-finished chamfering and interior angles. It also features a balance cock engraved by one of Lange’s master engravers, with each watchmaker's unique engraving style identifiable. The bridges and plates are made from German silver, an alloy of copper, nickel, and zinc, which develops a subtle patina over time.

The movement is not the only part of the watch benefiting from the great knowledge and high-quality manufacturing of the German brand. The rose gold case is perfectly adapted to welcome the beautiful silver dial, thanks to a reasonable 35.9mm case size. This allows the watch to maintain its classy, dress-watch aesthetic. The dial, with its beautiful grainy texture, features some of the most perfectly applied text and numbers available on the market. The level of finishing offered by Lange on watches at this price point is phenomenal, explaining why the brand has gained collectors’ interest over the past years.