BeadSmith No-Tangle Thread Bobbins, 3-1/2, Pack of 4 Has a patented, protective locking feature which prevents threads from unraveling. Stackable and made from soft plastic Bob-EEZ are great for macram, kumihimo, intarsia knitting, and other crafts Use multiple bobbins to secure loose ends as you work Pack of 4, 3-1/2" bobbins