My customers asked if I could use black satin rattail cord instead of cotton cord and I didn't realize how easily it catches on things and planned on using regular large heavy jump rings as bails - and the opening in the jump ring caught on the rattail and snagged it - the more I tried to fix it the worse it got. Then I found these awesome soldered closed 9mm round links from Rings N Things - they are great! The metal cord ends and lobster claw clasp actually fit through the link and no more snags on the rattail cord!! Solved a big problem!!