Light Weight:Round Shape and Very Light Weight(about2.0g ),even Delicate Necklaces Fit Perfectly.It Will Keep the Clasp in Back,Means Won't Pull Your Necklace Back. High Grade Materials:This Magnetic Jewelry Clasp is Made of Stainless Steel,which is Non Rusting, Waterproof, Sturdy and Never Fade.It is Free of Lead,Cadmium,Nickel Release Free. Unique Design:Built-in Magnets and Interlocking Ridges(Uniquely Designed Locking Structure),can Keep Clasps Securely Clasped.Meanwhile,it is Easy to Install on the Necklace and Easy to Put on or Take Off. Super Easy to Use: Just Attach Their Two Parts to Each End of the Necklace, and when They Come Close to Each Other, the Magnets Hold Them Together and Hold Them Firmly.The Magnetic Clasp is Suitable for Making Jewelry, Such As Necklaces and Bracelets, and It is Also the Best Choice of Gifts for Loved Ones. Perfect Size: This Magnetic Clasp is About 36.9mm*9.0mm(1.45"*0.35"), Thickness is Approximately 3.2mm(0.13"),the Appropriate Size Fits Most Necklaces and Bracelets.Note That It May Extend Your Necklace or Bracelet by Approximately 36.9mm/1.45".