Easy to use, lovely design. When closed with pliers around cord, tiny teeth inside the "petals" grab the cord for a secure hold that looks clean and neat.
TIP: When using with silk cord or ribbon, be sure to tie a small knot in the cord, then slip that into the clasp using the tip of your round nose pliers or the end of a paper clip. Then pinch the "petals" closed upon the knot. For a little more security add some Hypo Cement in the tip.