The Gypsy Gripper is designed with two suction cups that attach to any smooth ruler surface. The Gripper ensures that even pressure is applied to the cutting surface so you can relax and rest your hand comfortably over the handle. Since no death grip is required, this tool is recommended for anyone with hand issues such as arthritis and carpel tunnel. Your hand is always away from the rotary cutter so your fingers are out of harm’s way, making this a must have for any new or young quilter! Note: The ruler must be at least 4 inches wide and 12 ½ inches long - excluding the hang hole - to be effective.