What do you use to bind polymer items to metal findings?

I want to start my own shop on Etsy, I've got bracelets, necklaces, and chain links and stuff like that done but I also want to to things like cell phone cases and hair pins and I want to know what people you to bind the polymer clay charm to the metal finding (hair pin, ring, barrette, etc), is it strong and durable I wouldn't be able to stand myself if I were selling bad quality items to people.