Luminance 6901 was created for professional artist, designers and illustrators. Highly recommended for mixing, blending, shading, burnishing (with or without the use of white pencils) and gradations. Uniform colors that lay down with no "Wax Bloom." 100 colors in highly concentrated pigments which are permanent, water-resistant leads. Each color sold separately. 3.8mm, 8 ply round barrel constructed with premium grade California Cedar for maximum strength. Certified: FSC, Forrest Stewardship Council. Complies with ASTM D-6901, Imported. Smooth lead requires the use of a sharp, high quality pencil sharpener.