Use Super Bobs MasterPiece Prewound Bobbins in embroidery, sewing, quilting, or thread painting projects. This 12-pack of bobbins holds 80-yards of 50-weight, 2-ply Egyptian Cotton Thread. Super Bobs MasterPiece Prewound Bobbins have a uniform tension that will allow you to achieve more consistent and even stitches, giving your finished projects a more professionally finished look. These class 15 plastic bobbins are reusable and available in a multitude of colors to suit any project.