1. The thread bobbin holders are made from quality plastic which is durable to last for many years. Non-fading, elastic, and not easy to break.2. Bobbin holders are designed to avoid thread twined. These spool clips are organizers that keep your sewing room neat, nice, and clean.3. With these thread spool holders, we can firmly hold thread spools to keep thread tails from unraveling and losing tension. Suitable for most of the home embroidery and sewing machine thread spools, except commercial, and industrial spools.4. Use your fingers to open the bobbin clips and hold them until you clamp the thread tail. The bobbin clamps will tighten the thread and will not let it tangle even if you drop it.