Crown Vintage FLAT Glass Pocket Watch Crystal 21-4/16 (~47.9mm) - NOS

Crown Vintage FLAT Glass Pocket Watch Crystal size 21-4/16 = ~47.9mm with a thickness of ~3.2mm.  Very thick dead flat profile with a steep bevel, typical of what originally came on large vintage pocket watches, specifically those made well before 1900.  Not pristine as there are nicks along the top rim but otherwise very nice. Special procedures must be observed to see these installed without introducing flaws. While still likely well over 100 years old, in my 40 years of experience with them I've not found the older crystals to be any more or less brittle than anything you could find today. That said, they are quite likely very dirty and need serious cleaning.  I have a supply of crystals that numbers in the hundreds of thousands so I can usually supply just about any size Watch Crystal you need (glass or acrylic) so feel free to inquire. Images do an adequate job of representing the item.