What does “ISO” mean?

ISO stands for In Search Of. It works much like WTB: the poster is looking for a particular watch or part. It tends to be used in a slightly softer way, sometimes for harder-to-find items such as a specific vintage reference, an original box for an older watch, a missing bracelet link or a particular dial variant.

Dealers watch ISO posts because they often point to items that are not sitting in normal stock, where a bit of searching can turn into a sale. If you answer an ISO post, be precise about what you have and how it matches the request, for example whether a box is the correct style for the watch's era or whether a link fits that exact bracelet reference. Close is often not good enough for these buyers, so clear photos and reference numbers help.

A typical post: “ISO: one original link for a Rolex Oyster bracelet, matching the bracelet reference stamped on the clasp, needed to complete a customer's set. Genuine only, please send photos.”