THESE ARE VERY SMALL!!!  Please be sure it will work for you, so I don't receive anymore issues
                                                      them being too small. Thanks!
This clasp is:    

• 4.5mm diameter X 15.5mm, 5mm Spring Ring clasp
  3/16" X 5/8"
           a dime coin is 17.5mm
• DOUBLE spring rings on item 265183419576
• Item 154477976571 comes with 6mm spring rings
• DOUBLE 6mm spring rings on item 154478030417
  
  
• 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.
  
  
• Clasp WILL be slightly attracted to magnet, as will other clasps.
  Their internal springs are steel. Rest assured these are 14k Gold FILLED 1/20
  
  
• 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