In a Pat Speth class (Nickel Quilt lady), she mentioned that she used to use the sandpaper dots but they scratched the other rulers. She now buys the cheap rubber shelf liner at the Dollar store (don't use Rubbermaid - too thick) and cuts a little piece to place under the ruler when she is cutting fabric. The ruler no longer scoots, you have to pick it up and move it. Works great. One package of shelf liner would last forever. She had a piece that was about 1"x2" piece for her 5" square ruler and maybe a 2"x6" for her long ruler.