Real Gold plated base metal. Just attach one of these to the end of your necklace using a jump ring or a split ring. Then you can fasten the clasp on any part of the chain and Voila! you have an adjustable necklace. Quantity: 5 extenders. Includes lobster clasp. Measurements: each extender is two Inch long, plus an extra 12mm clasp on the end. Chain is 3. 4mm wide.