Unlike conventional oil colors, Paintstik Oil Colors are dry to the touch in 24 hours! They are perfect for sketching out shape, composition, and color without messy palettes or mixing cups. Colors can be spread or blended with a brush, knife, or Colorless Blender. The colors are completely compatible and can be blended with any oil paints. Use turpentine to thin. Paintstik colors are self-sealing — just peel off the film before each use. There are no unpleasant odors or fumes, so you can paint virtually anywhere, at any time, on almost any surface — canvas, paper, wood, plastic, metal, and fabric. Paintstik colors are non-toxic and hypo-allergenic. A free color chart is available on request. Each stick measures 4-1/2" long × 5/8" in diameter.