Neewer&reg; Silver 22mm Stainless Steel Push Button Butterfly Deployment Clasp for Watch Band Strap This replacement auto butterfly clasp fit 22mm leather, metal or rubber band which is not included. The top two butterfly wing sections fold down onto the bottom portion and meet in the middle,known as hidden clasps because only the push buttons can be seen when it is completely closed. The push buttons are used to release the inner catch and open the clasp. Very easy adjustment with spring bar locking closure. Double lock release with screw attach to strap.