Versatile Rolling RulerEasily draw horizontal and vertical parallel lines. Draw circles up to 28cm in diameter. Draw angles with the built-in protractor. Draw curves, arcs and more geometric figures. Drawing roller rulerBuilt-in roller, smooth sliding, stable drawing and not easy to tilt.There are parallel scales, various formulas and conversion factors on the roller for easy viewing at any time. Transparent Scale RulerThe printed black scale on the ruler is clear and easy to observe. Marked in both metric and inch. The transparent ruler allows you to draw without ignoring certain graphs or important texts. Material and precautionsMade of impact-resistant plastic, lightweight, easy to carry, practical and durable.Note: This roller ruler is only suitable for use on relatively low-friction surfaces. such as drawing paper and canvas, and not suitable for use on excessively smooth surfaces. Widely usedWhether you are an artist, student, designer or architect, this drawing parallel ruler is a good helper for your work or study. It can help students develop their surveying and mapping skills and spatial imagination to meet different needs. Wide range of applications --- The rolling drawing ruler is very suitable for students, teachers, artists, designers and architects to draw and measure various geometric figures. Material: polystyrene Colortransparent Size: length 36 cm, width 7.2 cm, height 2 cm Weight: 90g Objective: used to draw horizontal and vertical lines, circles, arcs and parallel angles. Packing list: 1 x Rolling Parallel Ruler