Porous-Point Pens by Pentel. Details:The Pentel Sign Pen has non-permanent water-based ink and an acrylic fibre tip which creates a smooth writing feel and a tip that remains durable throughout its use. The designer's choice - ideal for graphics and illustrations. It has 2.0 mm tip which gives approximately 1 mm line width. Made from at least 83 per cent recycled material. Pentel has certainly withstood the depths of time as it has been manufacturing and selling art materials for more than 60 years. Established in 1946 as The Japan Stationery Company, the organisation started by selling school supplies such as water colours, crayons and oil pastels. Artists, students and craft enthusiasts are able to choose from a wide variety of wonderful Pentel Arts products, made from the suitable materials and available in different colours.