Basically it's a little decision for your cell phone our tablet. The charm hangs from a string (lanyard), which it's attached to the dust plug. You put the dust plug in the hole where the headphones area attached. This keeps the dust from getting in there and possibly inside of the phone/tablet. I can take a picture of mine on my tablet and upload it to the auction.
I hope this info helps you understand what it is and how to use it. Thank you for asking and your interest in my auction.