The present invention improves the usability during angle measurement by displaying the angle scale on both sides of the protractor by improving the conventional protractor, and by forming the base line and display length integrally, it is possible to reduce the confusion and error during the angle measurement. Allow measurement through construction.;An angular scale is displayed on both sides of the protractor, but the angular scale on the front side is displayed starting from the left side, and the angular scale on the back side is displayed starting from the right side, and is an improved protractor which integrally forms the base line and the length.
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