Elastic Cord: This is a must have when working with children to string beads for jewelry. You don't have to be overly concerned with the length you are stringing, since it is just tied with a knot and stretches open to go over their head or hand when done. This elastic cord is .7mm in diameter in a translucent clear color. It comes on a card of 5 yards. It's a good and strong cord, but it is recommended that you completely cover the knot with a spot of good glue, or the elasticity itself will cause the knot to eventually come untied.