Clam Shell Bead Tip 3.5mm Cup Sterling Silver Filled (4-Pcs) This Sterling Silver Filled Clam Shell Bead Tip features a 3.5mm Cup, and is designed for attaching to Clasps and End Caps. Slip your Silk Bead Cord, Elasticity Cord, or any other Stringing material through the hole in the bottom of the Bead Tip, tie your knot, close the two halves together, and you've created an attractive Bead which hides the knot. Cup size: 3.5mm Hole Diameter: 1.00mm