Check the listing for details. 4.5mm 14k MAGNETIC DOUBLE CLASP Converter Yellow SOLID Gold Necklace Spring ring. Color: Yellow, Condition: New with tags. Listed at 45.00 USD. THESE ARE VERY SMALL!!! 4.5mm spring rings are about as small as any jewelry comes with. Item 265158506468 comes with 6mm spring rings on both sides. This clasp is: 4.5mm diameter X 20mm, 4.5mm Spring Ring clasp 3/16" X 3/4" a dime coin is 17.5mm In our opinion, suitable for chains up to 25grams. You be the judge for yourself. No hassle returns. It is strong enough to hold one side & slide all around the Nickel without it even starting to come apart. Spring ring and other clasps WILL be slightly attracted to the magnet, as their internal springs are steel. Rest assured these are solid 14k NOT responsible for any losses due to clasp failure. USE AT YOUR OWN RISK if you use a PACEMAKER, INSULIN PUMP, OR DEFIBRILLATOR etc...Thanks Weight: 0.69grams each 14k White Gold are item # 153394921198 & Rhodium Plated 153411261524. DO NOT clean Magnetic Claps in ULTRASONIC cleaners as it will reduce the strength of the magnets.