Please Sir…

       …it just came apart in me hand. 
It was the far back left side one here. Most of them, of the ones I eventually manage that is, have a "Key" if/when you can find it.  IF this one has a key I don't recognise it as such.
AND
       It did, quite literally, drop to pieces, while I was key hunting.  It's easy to see where each piece goes; it's practically impossible, thus far, to hold them all in place.

( : ¬ o)