Clear-Glide is a high-tenacity polyester filament bobbin wound on a plastic flange spool. Designed for today's home sewing (drop-in) bobbin case Fits most standard home drop-in machines (Style L). Works great with machine thread sensors. Plastic bobbin not affected by humidity or oil. No uneven tension caused by distorted paper sides. More stitches per bobbin, saves you time. 135 usable yards per bobbin. Available in a wide range of colors. Runs clean - no lint buildup.