Ingenious part! Many good special features!

Ingenious protractor, measuring angles is much easier and circles can be made in any color, without always carry around a circle. Have now bought a second time to me, the old has withstood for 5 years in my pencil case. It is supposed to be unbreakable, but is only partly true. But lasts much longer than conventional through Goedreiecke.
The special features are really useful, the idea genial, so there 5 Star.