Koh-I-Noor Progresso woodless pencils are highly pigmented pencils that offer excellent light permanency for creating vibrant, durable pieces of art. Another key component of the Progresso woodless pencil are the special oils used in the pencil lead. These oils, along with other binders, allow the Progresso woodless pencil to create dense, even strokes without the use of heavy pressure. These 7.6mm lead diameter are not encased in wood like other pencils; this reduces the loss from sharpening and maximizes the use of the entire lead. The end result is water-resistent, non-toxic and suitable for all artists.