The Trim-itâ?¢ Rulers by Lori Holt of Bee in my Bonnet are non-slip and easy to use for trimming up your blocks after piecing, applique or embroidery. Use the diagonal lines to easily center your block when trimming and and use the colored outside 1/4" seam allowance marks to help you see what will show of your block after sewing it into your quilt. The ruler has aqua and denim markings printed in 1" grids marked in 1/8" and 1/4" increments.