Zenith El Primero Lightweight Limited Edition (Video) Written byMark BernardoNovember 4, 2013 In 2010, Zenith introduced its El Primero Striking 10th chronograph, whose highlight feature was a sweep-seconds hand that made 10 jumps per second and a complete sweep of the dial every 10 seconds. This year, the brand introduces a version of that watch designed for maximum lightness called, appropriately, the El Primero Lightweight. The new Zenith El Primero watch, limited to only 100 pieces, is distinguished by the materials chosen to make the watch as featherweight as possible yet still sturdy and reliable. The case has an inner structure of ceramized aluminum and an outer coating of carbon with the familiar checkered pattern. The movement uses titanium for its mainplate and bridges, resulting in a caliber that weighs a mere 15.45 grams (as compared to 21.1 grams for a comparable movement with those components made in the traditional brass). Zenith chose titanium, a metal used in aeronautics and known for its lightness and resistance, for the parts of the movement that are normally the heaviest: the mainplate, barrel bridge, balance bridge, pallet bridge, pallet-wheel bridge, and chronograph bridge. The movement, Zenith’s El Primero 4052 W, also includes the double chronograph wheel made of silicon, a feature the company first used in its first El Primero Striking 10th model. In this new Zenith watch, the lever and escape wheel are also made of silicon, a material prized for its lightness and anti-magnetic properties. The case of the Zenith El Primero Lightweight is slightly larger than that of its predecessor, the Zenith Striking 10th — 45 mm in diameter as opposed to 42 mm — and made of ceramized aluminum coated with fine black carbon. Ceramized aluminum is lightweight yet sturdy and hard (1,800 Vickers on the hardness scale, compared to 160-200 for 316L stainless steel). The chronograph pushers are made of titanium and the aerodynamically sculpted lugs flow into the integrated strap, which is made of black rubber (interior) and high-performance Nomex synthetic fiber (exterior) and features a triple-folding clasp.