Hercules Metal Brainteaser by Bits and Pieces.  The Hercules tray brainteaser consists of colored metal pieces, identical in size and shape. There is only one way to fit them all into the 4-1/2" square wood tray. Designed by Jean Claude Constantin. Solution included.  The puzzle has never been used still in the factory sealed wrap.

“Unlock the brilliance within with this mind-bending puzzle!”