Not quite a brush and not quite a palette knife, Catalyst tools are crafted from flexible silicone to allow artists a new form of expression. Designed for use with heavy-bodied paints, they are ready for oils and acrylics. Because they are heat-resistant, they excel with encaustics. Artists are using them with plaster and clay. Made of FDA approved silicone, Catalyst tools are great for food crafting. Silicone is easy to wipe clean and is solvent-resistant. Cleanup in most cases can be done with mild soap and water.