Creative Grids® 30º Triangle Ruler - CGRSG1 

Sew together 12 triangles to create a complete circle; 6 to create a half-circle; or 3 to create a quarter-circle. Make pieced arcs and circles up to a finished size of 38 inches. This 19 1/2" 30° triangle includes 30º, 45º, and 60º angles. This triangle may be used as a companion to the Circle Savvy Ruler, Item #CGRSAV1.