Fil-Tec "L" Type Plastic Sided Pre Wound White Bobbins. Qty 100Fil Tec "L" Type Pre Wound Clear Glide White Embroidery Bobbins. Plastic sided bobbins that contain 125 yards of machine embroidery bobbin thread. Safer for machines with sensors as there is no build up of cardboard dust in the bobbin case that would prevent sensors from working. Pre wound bobbins are more convenient and hold much more thread than bobbins you wind yourself thus speeding up your embroidery stitchout. Qty: Box of 100 white bobbins