Stop Beads Inserts Silicone Rubber Donut Spacers Fits European Charm Bracelet. Quantity: 500PC Beads are 6mm round silicone Donuts with a 2.9mm stretchable hole. We have tried them on Troll, Pandora, Dione and 2 different Knock of chains These are ment to use under a clip over stop bead.