What does “SS” mean?

SS stands for stainless steel, the most common material for watch cases and bracelets. In listings it is often used to separate an all-steel version of a model from two-tone or solid gold versions of the same watch, for example “SS Datejust” versus a Rolesor version.

Not all steel is the same. Many brands use 316L stainless steel, while Rolex uses its own 904L-based alloy, which it calls Oystersteel. These differences affect corrosion resistance and how the metal takes a polish, but for most buying and selling purposes SS simply tells you the watch has no precious metal. Steel sports models from the major brands are often among the most sought-after watches on the secondary market, so the material can matter a great deal to demand even though the metal itself is not valuable.

Typical usage: “Royal Oak 15510ST, SS, blue dial, 2023, full set.” Brands often include the material in the reference or its suffix, such as ST for steel at Audemars Piguet, which helps confirm what you are looking at.