The original Clearprint vellum pads were first designed for architecture and engineering, 1000H Design Vellum is the industry standard. Pencil and pen lines come out sharp and clean with no feathering edges and no ghosting. Retains strength, stability, transparency, and printing qualities under exposure to heat, light, and atmosphere. It will not become yellow, brittle, or opaque with age. Compatible with a wide range of fine art media.