Designed for Appliqué, Bobbin Thread, and Quilting. Designed with award-winning quilter Libby Lehman, SuperBOBs are L-style and M-style prewound bobbins, wound with the Bottom Line thread. Available in 46 colors, SuperBOBs are for quilting, sewing, and embroidery. The lightweight, blending colors are easily matched with any top thread. SuperBOBs are cardboard sided.