The steel watch has acquired a prominent position across almost all of the collections of the Grande Maison. Steel is an alloy composed mainly of iron and carbon, the exact content of which is essential: below 0.02%, it is iron, above 2.1%, cast iron. Once deemed to be common by watchmakers, under the impetus of various reputed names in Haute Horlogerie, a certain type of steel has become a noble metal prized for its many qualities. Indeed, the steel watch is amagnetic and highly resistant to corrosion. Biocompatible, it also boasts excellent mechanical strength. There are different types of steel, from non-alloyed and low-alloyed steel to, on the contrary, steel that contains many alloying elements. Jaeger-LeCoultre uses a high-quality stainless, that is to say highly alloyed, steel, to dress the cases and bracelets of numerous watches across most of its collections, notably the Reverso and Master.