How much time do you spend untangling your Apple earbuds? Come on, be honest... every time you pull them out of your pocket, they're coiled into a nice neat knot that you spend fifteen minutes trying to unravel, when you could be listening to music.
This hard case stores a set of Apple earbuds (or maybe even other earbuds, who knows...), wraps the cable, holds it from unwinding, and protects the whole mess... plus offering you a handy lanyard that you can clip to whatever, or attach a carabiner to. Sky's the limit!
Deraft all the parts, and carefully clean up the case half pivots. Ream out the hinge through hole, knot your lanyard and pass it from the inside out to set it. Snap the case halves onto the hinge.
Snap the hinge into the spool. The hinge should detent into the spool, and then the case halves should click home. You may want to gently sand the corners of the snap groove in the spool to ease up on the aggressiveness of the case half snaps, depending on the tolerances of your printer. (Otherwise you might have to use a screwdriver to split the case a few times, to wear it in.)