This metal compass and protractor set is everything you need for your math and drafting classes. The metal compasses in this set features a ball bearing design that helps create accurate circles up to 12" in diameter. With better control and a positive pencil lock, you can rest assured that you will create perfect circles and curves everytime. Complete with pencil, inch and centimeter guide. Each set also includes a plastic 6" protractor that boasts sharply defined graduations, making it easy to read. The edge of the protractor also features a 6" ruler making sure all your needs are met with this set!