Roll Dough to Perfect Thickness for Cookies, Pie Crusts, Puff Pastry and Biscuits. When a recipe says "roll dough to 1/4" thickness"¦," how do you know when it's correct and how can you be sure it's completely uniform? Now it's "easy as pie"! Just select the correct and how can you be sure it's completely uniform? Now it's "easy as pie"! Just select the correct pair of rings, slip them on the rolling pin barrel, and start rolling. You'll get the correct thickness for cookies, pie crusts, puff pastry, and biscuits. Included are four sets of color-coded rings for 1/16", 1/8", 1/4", 3/8" and easy directions.