Square Up Ruler, 12-1/2"The OmniCraft 12 1 2" square ruler is used to "square up" quilt blocks, needlework or other crafting mediums. It includes measurements from 1"" to 12 1 2"" Use with a rotary cutter or a straight edge blade The OmniCraft 12 1 2"" square ruler has the following standard Omnigrid features: Edge markings for accurate measuring Laser cut edges for smooth, deep cutting Patented double sight lines that show up on light and dark fabrics Heavy duty durable