Stop tangling and fraying with this synthetic thread conditioner. The box has an easy open lid and you just slide your thread across the top. Thread Heaven creates a slick coating that acts like ball bearings so it helps the threads slide through your fabric. It works especially well on metallics, silks, and rayon threads to keep the strands together & stop fraying as you stitch. Thread Heaven is chemically inert and will not react with your fabric or fibres.