3 PACK, 14k Gold 4 mm Magnetic Clasp for Light Necklaces USA, Square Edge 14k Gold w/ the most powerful rare earth magnets on the market today perfect for people with long nails, arthritic, limited use of fingers nickel free, allergy free and wont turn your skin green, wont cheapen your jewelry Use this Clasp as a Permanent Replacement of the existing Conventional Clasp, so you wont add much to the length of your chain 4 and 5mm magnetic clasps are NOT strong enough for bracelets, we only recomment 9mm size for that porpose, and if the bracelet isnt heavy