Specialised clip on lens are perfect for beadmaking and other lampworking activities using soft (moretti) glass. Clip-on lenses fit securely to your round or oval style prescription glasses: they'll protect your eyes AND allow you to see variations in flame and glass colour that other shaded safety glasses block out. Our staff experts say that seeing these different shades of colour make it much easier to achieve the effects you want in your creations The Phillips 202: ACE is a new material that utilises rare earth oxides to provide unique colour enhancing characteristics; it's an advanced version of didymium glasses. Lenses measure 50mm thick. Not recommended for borosilicate work.