That said, they are quite likely very dirty and need serious cleaning. Images do an adequate job of representing the item. Fulton Watch Crystal Corp Fit-Tite Catalogue No. 2 – reprint. Illinois Watch Co Materials Catalog Dec 1923 – reprint.
VTF Vintage Glass Pocket Watch Crystal 17-12/16 (~40.0mm) – NOS
That said, they are quite likely dirty and need serious cleaning. Images do an adequate job of representing the item. Fulton Watch Crystal Corp Fit-Tite Catalogue No. 2 – reprint. Illinois Watch Co Materials Catalog Dec 1923 – reprint.