The necklace shortener is made of base metal with 18k yellow gold plated over. You can let the necklace go through and put it either in the front as a center piece or on the back functioning as a shortener only. It is perfect to make any necklace to be a choker or shortener.
If you are allergic, you can checkout all other shorteners in our pearl brooch department. They are make of 925 pure sterling silver for $9 – $15. We do have quite a few different styles and selections in stock. And here is the link.