Nowadays this view can be obtained since the Datograph Auf/Ab; the movement was improved and a power-reserve screen was added. There’s also a version with a perpetual calendar, the Datograph Perpetual.The Lange 31 has been named for its power book: an astonishing 31 days. These include two stacked barrels, each having a strong mainspring that is 1.85 meters long, a few times longer than a standard mainspring. The barrels are 25 mm across and occupy three-quarters of the motion diameter.With a power book this long, and springs this strong, the amplitude of the balance would diminish significantly over time if nothing were done to keep it. However, Lange has set an innovative constant-force device involving the twin mainspring barrels as well as the escapement. It guarantees a constant flow of force, independent of the tautness or slackness of the mainsprings. It achieves this with the aid of a helical, pretensioned spring (a so-called remontoir spring), which can be retightened every 10 seconds, and, over the following 10 seconds, provides energy to the escapement. There are minimal changes in torque during the 10 seconds, but the energy conveyed remains nearly constant on average during the 31 days. When that period has elapsed, an additional mechanism simply stops the watch.
While much of the watch industry is making smaller watches, out of modesty in straitened times or just following the fashion of the day, Breitling is admirably hewing to its traditional formula of oversized sports watches. While often overbuilt and designed like an invading army, Breitling’s biggest watches do have a certain appeal, exemplified with the newly announced Avenger II Seawolf Blacksteel.
The steel case is 45mm in diameter and 18.4mm high (making it as thick as most chronographs), with the “Blacksteel” moniker derived from its black carbon-based coating (a type of diamond-like carbon or DLC) that is scratch-resistant (Breitling has made a slew of Blacksteel limited editions in years past). Rated to 3000m, or 10,000ft, the case includes a a helium escape valve for the improbable activity of saturation diving.
The dial is a bright yellow, with the rotating bezel sporting Breitling’s trademark rider tabs at the quarters. And the movement inside an the Breitling calibre 17, which is actually a basic but robust ETA 2824 that is chronometer certified.
The Avenger II Seawolf Blacksteel is limited to 1000 pieces with the retail price yet to be revealed. The ordinary stainless steel version of the same watch retails for approximately US$4000, so expect this to cost slightly more.