Another simple but brilliant invention. The ruler has an integrated roller that allows you to smoothly pull the edge across the paper and it's calibrated so that you can measure how far you are dragging it vertically. That makes drawing parallel lines an absolute doddle. Add an integrated protractor, pencil holes for drawing vertical lines and circles and you've got a superb aid to drawing of all types.

• 2-pack set of rulers; 1 x 30cm, 1 x 22cm
• measures both vertically and horizontally
• built-in protractor
• holes for compass, max 60cm diameter
• easily create geometrical figures including circles, ovals, triangles, and much more
• ideal for DIY, technical drawing and home study
• pencil holes for vertical lines
• integrated protractor
• rolling integral ruler in cm