Synthetic burlap is one of the more commonly used utility fabrics inside modern furniture. It provides a barrier between your foam and springs and jute, preventing those structural materials from cutting through your foam over time. You don't have to use this material though. Any sturdy material will do. Recycled burlap, canvas, duck cloth, or heavy duty upholstery fabrics all make great barrier fabrics for your furniture projects. This one is a cheaper material and comes by the yard. It tends to be fuzzy on one side and slick on the other. Spray adhesive will not hold foam and batting to this fuzz well. Keep that in mind when choosing which side faces up.