Perfect Half Square and Quarter Square Triangles Ruler. This all-in-one tool is for creating perfect half and quarter-square triangles for quilting. This cut-through ruler has measurements starting at 1-1/2 inch and continuing to 6-1/2 inch in 1 inch increments and 45 degree angle markings. Ruler is constructed of clear flexible acrylic and measures 12-1/2 by 10-1/2 inches. Made in USA.