Omnigrip 2-1/2-Inch-by-18-Inch Non-Slip Quilter's Ruler
Omnigrip Non-Slip Quilter's Ruler For Short Strips and Sashing features a left and right hand numbering and angle system.  Diagonal line for triangle cuts.  An extra 1/2 inch on two sides for seam allowance.  Also features 30, 45, and 60 degree angle markings.  Size:  2.5 by 18 inches.