18x13mm Rhinestone rimmed pendant setting.. I like this setting very elegant going to work well with lots of things and it includes a bail. I will note however it runs on the small side. I tried a number of gemstone cabochons in it which run large and they would not fit properly. Resin cameos are usually a bit smaller and some of them fit but realistically plan on shaping them or trimming just a bit to fit them correctly. If you have a particular match in mind I am happy to check the fit for you just ask.