This is a keychain lanyard.  It holds keys.  It snaps to things.  I use mine to snap to my belt so my keys don't fall to the bottom of my pocket with all the other things in there. I've also seen it snapped to a bag handle so the keys stay accessible.  The clasps are either solid brass or stainless steel which is probably overkill for what is is, but that's just how I roll.  It's classy, cool, simple, and useful.