Crafters Workshop TrueCut Non-Slip Ruler Grips, 30/Pkg Apply these little rings to the back of any ruler to increase safety and cutting accuracy by preventing slipping They are transparent so your project visibility is not impaired These rings work on any ruler and are great for any craft that uses a rotary cutter This package contains fifteen 3/4x3/4 inch adhesive grips and fifteen 1/4x1/4 inch adhesive grips Convenient - Transparent for easy fabric visibility.