The A. Lange & Sohne Richard Lange 40.5mm watch. Model reference: 232.025. A. Lange & Söhne was founded in 1845 by Ferdinand Lange in the Saxon village of Glashütte. But the company owed its success not just to Ferdinand’s watchmaking genius, but also to that of his sons, one of whom, Richard, became joint owner in 1868 — hence the brand’s name. Richard Lange is known particularly for the invention of a balance spring made with a beryllium alloy that is still in use in many watches today. The modern company named one of its finest collections after Richard. This is a platinum A. Lange & Sohne Richard Lange with a scratch resistant domed sapphire crystal with anti-reflective coating. It has an exhibition sapphire display case back secured with 6 screws. The 40.5mm diameter solid three-body case is 10.5mm thick with downturned lugs, and angled bezel are polished. The dial is matte silver with black painted Roman numeral hour markers and an outer minute/second chapter ring. It has rhodiumed gold sword hands with a blued center sweep seconds hand. It has a 38-hour power reserve at full wind, and it’s water resistant to 30 meters/100 feet. The mechanical manual winding A. Lange & Sohne caliber L041.2 movement is rhodium plated. It’s constructed with 28 jewels, a shock absorber mechanism, and a straight-line lever escapement. It has a large balance wheel with a patented balance spring (the spring is produced in-house and is secured by a new clamp that allows for much simpler adjustment). It includes a hacking seconds movement for complete accuracy that stops the seconds when the crown is pulled out. The mechanism oscillates at a frequency of 21,600 vph (3 Hz). Included is a hand-stitched, navy blue crocodile strap with an A. Lange & Sohne platinum ardillon buckle. Case, dial and movement signed A. Lange & Sohne. The watch comes in original packaging, with a set of documents.