The most popular quilting ruler! The 6-1/2" Triangle Square Up Ruler makes perfect half triangle squares and quarter triangle squares in sizes up to 6-1/2". Fully illustrated and detailed instructions are included. The ruler is marked in two colors for easy reading, is made of heavy gauge acrylic, and is laser-precise. Convenient 1/8", 1/4", 1/2" and 1" lines for precise measuring.