Any building buff will love this scale ruler pen. This retractable ballpoint pen is made out of a scale ruler, which is a specialized ruler used in architecture, engineering and construction. The scale ruler is used to make or measure from reduced scale drawings such as blueprints and floor plans. This pen is in the traditional triangular shape of the scale ruler complete with a range of calibrated scales (ratios). A convenient tool for writing, measuring and marking up those blueprints. Designed by Shigeru Ban. The scale ruler pen has a fine point and you can order additional refills too. Made in the USA. Found at UncommonGoods.com.