Val Cox Frit is premium furnace glass (96coe). Furnace glass contains precious and semi-precious metals to achieve its intense color. These metal oxides also make furnace glass more elastic. This means that even though Val Cox Frit is 96coe, it is compatible with Moretti/Effetre/Vetrofond (104COE) and Bullseye (90COE) when used sparingly. A good rule of thumb is 5% frit to the weight of the bead. Even if you are working in 96coe, applying or encasing a small amount of frit not only works best, it looks best. The colors can be intense so a little goes a long way.