Princeton Catalyst Blades are more flexible than a palette knife and spreads like a brush. They are mounted on artist brush handles offering a blend of tradition and innovation. Catalyst Blades work like palette knives while holding paint even better. With 6 different blade tips to choose from in 3 different sizes each (18 options), the texturing possibilities are almost limitless. Made of FDA-approved silicone with easy to wipe clean and is solvent resistant. Designed to use with heavy-bodied paints, oils, acrylics, and water-miscible oils. Ideal for colour shaping & texturing. Stiffness – 5 on 5