The formula is secret the pencil is world-famous.Staedtler's success story began over 180 years ago, with manufacturing pencils. To this day, first-class manufacturing processes and sustainably sourced materials guarantee outstanding and consistent product quality. Staedtler Mars Lumograph water soluble pencils are specially made for both drawing and painting on paper or canvas.Made with eco-friendly, sustainable harvested wood.Steadtler's committed to letting you enjoy your work and play with peace of mind. This permanent pencil kit is not only an ideal creative companion for drawing and sketching purposes, painters, hobbyists and crafters will benefit from the finest German manufacturing processes. Create a spectrum of radiant shades with 6 of the primary and most-used secondary colors, for a true spectrum of waterproof, permanent color shading and blendingWhether it's scientific or creative endeavors, in the home, office or classroom, Staedtler helps bring ideas to life.