Koala Ring Ruler Mini
Because there is no needle like a pivot-point compass, the Ring Ruler is safer for children and can be used without supervision. The Ring Ruler Mini also provides useful circular metrics like diameter and can also be used as a 360-degree protractor.Part Number: KT-10
The Ring Ruler Mini is a compact size-adjustable circle ruler. Simply click the zero point end into your desired size and it holds in place for easy measuring, marking or forming. Expanding and contracting the circle is as easy as pulling the ruler to form your desired size.