This 4-oz. bottle of Liquid Medium is used in conjunction with the Powdered Binder to make Modeling Glass. It's the same product as the Liquid Medium in the Starter Kit, at a better price per ounce. It’s part of a unique process that artists combine with powdered binder, water and their own powdered glass or frit. The resulting material has the consistency of clay, is smooth and easy to work with. It won’t stick to your hands or tools. The binder and liquid medium are food-grade and non-toxic.