Spark Plug Puzzle
a.k.a. Bougie, Get Charged
Available from a number of sources in 2013,
including Bits & Pieces and Puzzle Master,
who credit the design to Jean Claude Constantin.
(wood, metal pins, and spark plug, 3.75" x 2.2" x 1.1")
One of the metal rods is tight,
whereas the other one wiggles.
Position the puzzle as shown on the left below,
so that the rod that wiggles is facing forward.
Notice that if you look carefully,
the hole that the rod goes into on the right is larger than the left.
The puzzle will come apart by pushing the rod to the right,
having the left end of the rod come out, and then angling the rod out of the frame
(allowed by the larger hole on the right).
While applying pressure on the front rod pushing it to the left,
bang the puzzle hard down on a table;
this causes a piece hidden in the right side to drop down,
allowing the rod to be pushed further into the right and the left end to come out.
The puzzle apart is shown on the right below.