Here's a fun lenticular ruler for school or the office! Just tilt the ruler and the butterflies' wings will change to look as though they are flying. The faster you tilt it up and down, the faster the butterflies will fly! This flexible plastic ruler is 6" long and has centimeter markings on the top and inches on the bottom. There are no numbers, but the long tick marks denote the centimeter and the inch. They make great party favors and bookmarks too! Size: 6" long, 1-1/2" wide