Pack includes 12 shatter-resistant plastic combination compass/protractor/straight-edge/rulers. Students use this safe compass without any sharp points to create circles from 10-mm to 120-mm radius in 1-mm radius increments. Clear plastic provides students with a direct view of vertex points. For over 50 years, hand2mind has encouraged hands-on learning and discovery, driving deeper understanding and helping children unlock their full potential. Hand2mind specializes in math manipulatives designed to help students learn by doing. Particularly with learning shapes, hand2mind has you set with geometry sets, compasses for geometry, protractors, rulers and all necessary school supplies. From early math to middle school math, hand2mind has you covered with products designed to enhance learning in the classroom and the world around us. Through hands-on exploration and discovery we strive to find new ways to encourage students in math practice, literacy activities, STEM education and more!