The Pentel Sign Pen S520 Blue ink is the original fibre-tipped pen. It 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 - perfect for graphics and illustrations. The 2.0mm tips give approximately 1mm line width and it is made from at least 83% recycled material. It has certainly withstood the depths of time as is celebrating its 50th anniversary this year for office, college or home