These hooks are made up of two connected metal cups that have a hole between them and a hook. Also know as clam shells (because the two cups face each other like the shell of a clam), these are used to hold onto the knot at the end of a strung piece of jewelry, such as a beaded necklace. Then the hook is used to wrap around a clasp or jump ring. Bead tips are available in base metal, sterling, gold-filled, and gold.

You also might be interested in the links below:

Findings Beads & Caps
Headpins in different styles
Classic Earrings & Hoops
Sterling Silver Findings