A key component of the Polycolor pencil is the use of the special oils in the pencil lead. These oils, along with other binders, allow the Polycolor pencil to create dense, even strokes without the use of heavy pressure. The 3.8mm lead diameter is an added artistic value to these pencils. Polycolor pencils maintain excellent light permanency, creating vibrant, durable pieces of art. The broad edge is excellent for shading, while a finely sharpened point creates exquisite detail. These leads are encased in California Cedar for easy sharpening. The end result is a water-resistent, non-toxic pencil that is suitable for all artists.