A variety of the most popular full-size curves, conveniently packaged box for individual or classroom use. These plastic curves are great for detail work. They are heavy enough not to warp but flexible enough not to chip or crack if dropped from a tabletop. Each curve is molded of smoke grey-tinted 0.10" thick styrene plastic with double-beveled inking edges. From the Manufacturer: Westcott Drafting & Drawing Tools are some of the finest products of their kind for students and professionals. Our commitment to meticulous quality and cutting edge innovation in measurement and art materials has earned an unparalleled reputation.