The Stripology Squared, a slotted ruler by Gudrun Erla, has cutting slits every 1/2 inch so each strip you cut is the exact same size EVERY time! Follow the easy-to-read markings: squares for 2-1/2 inch cuts and stars for 1-1/2 inch cuts - no math required! Cut five 2-1/2 or eight 1-1/2 inch strips without ever moving the ruler. The Stripology Squared includes markings to square up half-square triangles, quarter-square triangles, and blocks in whole and half inch increments up to 12-1/2 inches.