This center finder is perfect for laying out bowls, trays and platters. Finding the center of irregular shapes to optimize yield is simple and easy. It is made from 1/8" acrylic with a center hole and clearly marked circles in 1/4" increments. To use, position on a blank, find the center, push an awl or nail in the center hole and then use a pencil in one of the diameter holes to trace a circle around the pivot point. Will marks circles up to 10 inches in 1/2 inch increments.