To avoid any confusion about what you will get when you order the Perfect Trim Ruler, it is a ruler designed to miter the corners when you are covering a piece of chipboard or book board with paper, fabric or other covering. Please do not confuse it with the "perfect layers rulers", the "perfect ruler" or the "perfect corner" ruler. When I named the product, there were not so many perfect rulers! The item you are ordering is almost 4" square. It is a piece of plexiglas that has laser etched lines to guide you in mitering the corners of your mini albums, books, journals or other projects. It is a quality made product, made in the United States. It is designed to be used with a rotary cutter, knife, or pencil and scissors as desired. You can use it for spacing your covers, or cutting a 45 degree "hinge" for box construction. Some clever artists even use it for a cutting edge for their tape. If you need to see a demo, check here for Kathy Orta of Paper Phenomenon, about 30 minutes in to the video. Or here for Kathryn at Kathryn Scraps. I will accept returns within 5 days of your receipt of the item. There will be a 25% restocking fee and the customer must pay the return postage.