Never worry about making accidents while squaring up or cutting fabric with your rotary cutter again! The quilt masters at The Grace Company designed these TrueCut rulers with a track on the edge that your TrueCut Rotary Cutter locks into so that you won't veer off and cut a not-so-straight line by accident. We all know that quilting is a science just as much as it is an art and exact measurements are what yields perfect seam and point matching. This innovative tool is excellent in helping you make sure that human error doesn't ruin your work!