On top part its a rotary action lead pointer no need to purchase extra 2mm lead sharpener. Technically a true geometric construction with Euclidian tools originally used by the ancient Greeks uses only a compass or a straightedge. Drawing Compass Geometry School Set Math Geometry Tools.
Geometry Math kit containing 6 pieces.
Compass lead refills 6 inch ruler 180 protractor 45-90-45 Degree triangle and 30-60-90 Degree triangle. 10 Virtual Tools for the Math Classroom Stepping Stones 20. Pen Geometry Set with 6 Inch Swing Arm Protractor Divider Set Squares Ruler. Plane Geometry is about flat shapes like lines circles and triangles.