SINGER Class 15 threaded bobbins offer the convenience of 12 pre-threaded bobbins. The polyester thread comes in a range of colors, including navy, white, black, gray and red. Each plastic bobbin has 50 yards of 100% spun polyester thread. Conveniently packaged in a see-through storage case, these bobbins are compatible with SINGER front load and top drop-in bobbin sewing machines, along with a number of other quality domestic sewing machines.Details:Includes multiple colors50 yd. (45.72 m) each12 bobbinsIncludes see-through storage casePolyester threadCompatible with SINGER front load and top drop-in bobbin sewing machines