The Ring Ruler™ is the first size-adjustable, circular ruler. It has been designed to make the drawing and measuring of circles and arcs a much simpler and more efficient experience by eliminating the cumbersome pivot-point system. Not only is the natural feel of expanding and contracting a circular ruler more ergonomic than using a needle compass, it is also quicker, safer and provides more the useful circular metrics of diameter and circumference (arc length).
One of the best features of the Ring Ruler™ is its simplicity. This makes it a great learning tool for children– especially ones too young to handle a circle compass.
Available in US Standard and Metric Scales