The eyes are sealed on the backs. I have sold thousands of my eyes with very little issues. I take a lot of time and effort in offering the best eyes of this nature. When I started making my eyes, I was using them in combination with vintage watch parts to make pendants. I found that the market was slim to none when looking for unique eyes. I started making them for other artists. I have a very strong following and demand for my eyes. I would like to see anyone who can do fired eyes that look even close to them.