The Omnigrid square triangle ruler is used to create quarter and half square triangles for finished quilt blocks; it has seam allowance calculations included in the measurements.

• Used to cut half-square and quarter-square triangles; seam allowances are included in the measurements, which are based on the finished size of the quilt block
• Use with a rotary cutter or a straight-edge blade
• Edge markings for accurate measuring and laser cut edges for smooth, deep cutting
• Patented double-sight lines that show up on light and dark fabrics
• Heavy-duty durable acrylic material
• Left- and right-hand numbering and angle system