The Perfect Ruler possibly was designed for papercrafts, though it is excellent for general crafts and certainly for patchwork. The secret? Ever have your ruler move when drawing a line, making your templates, measuring a distance etc? No more! The Innovative No Slip Grip keeps the ruler from moving on either the paper, plastic, fabric or whatever. Position the ruler, press the stopper bar to activate the grip strip, then draw or cut. Truly, at the touch of a button the Patented Grip Strip holds your project in place with NO slipping. IT ACTUALLY WORKS! Perfect cuts, trims and lines everytime. Whether you use a knife blade, stencil cutter or rotary cutter, your fingers are kept safely right away from the blade - comfortably and safely with its ergonomic design.