Extruded lumber crayons last up to ten-times longer than ordinary molded wax crayons. Fadeproof, waterproof, smearproof. Won't melt in direct sunlight. Will work on wet (green) lumber or dry wood, metal, concrete and most other surfaces. Hex shaped 4-1/2 x 1/2 in to fit lumber crayon holders. | Dixon by Toconderoga Carpenters Pencil