Pigmented graphite or wax-based refills for mechanical drafting pencils provide a range of hues for sketching, drawing, and note-taking. These colorful writing instruments often utilize standardized lead diameters like 0.5mm or 0.7mm, compatible with typical mechanical pencil mechanisms.
Adding color to technical drawings allows for clear differentiation between layers, systems, or revisions. In artistic applications, these materials offer vibrancy and precision, making them suitable for detailed illustrations and expressive sketches. The development of such colored leads followed the broader evolution of the mechanical pencil, offering greater utility and creative potential to users beyond standard graphite.