Dream Seam Class 15 prewound bobbins are filled with 80 yards of premium 50 wt. Egyptian-grown extra-long staple cotton piecing thread, perfect for piecing, sewing, and machine quilting. Quilters and sewists love how little lint and fuzz there is. It is also mercerized and gassed for improved strength and smoothness. A tight twist keeps the thread flat for precise, lay-flat stitches, ensuring strong, durable seams with no bulk. Available in 10 blending colors for sewing and quilting projects.