Bob Ross Brush Conditioner helps keep your oil painting brushes in tip top condition. This product helps condition your brushes and maintain their original form. Brushes should first be cleaned with Bob Ross Odourless Thinner then blotted dry. Use a small amount of conditioner and massage into your brush. Rinse off any excess conditioner with odourless thinner, blot dry and reshape the bristles. You may need to prepare your brushes by rinsing with thinner before use.