Used to put an ending on stringing material. Enabling you to add a clasp, etc. Feed stringing material through hole in bottom. Tie knot or use crimp so stringing material doesn't come back through hole. Close sides of "clamshell" with smooth flat nose pliers. Use round nose pliers to form hook into a loop. Add jump ring to loop & attach clasp, dangle, etc. 14 karat Gold Filled is composed of a solid layer of 14 karat Gold mechanically bonded to copper or brass. Thicker than plating so it will not chip or wear away. Treat just like solid 14kt gold, in terms of care & cleaning