Puzzlepedia™ Trick Locks
Trick Lock 5
This lock opens, but not in the usual fashion. Can you figure it out?
The mechanism to unlock this one is completely different from the locks you are used to. You have to discover the trick that keeps it locked. You're provided with two identical keys, but don't expect to just put them in the keyhole and open it.

Solution at Puzzlesolver.com
Purchase at PuzzleMaster.com
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