Original 3D Crystal Puzzle - London Bus The 3D Crystal Puzzle London Bus from BePuzzled is a sleek, translucent puzzle with 53 unique interlocking pieces Take puzzling to a whole new dimension with this double-decker London Bus Enjoyable to work on, challenging to complete and beautiful to display This 3D puzzle has a difficulty level of 2 and is fun for puzzlers age 12 and up Approximate assembled size = 4-1/2" 1-1/4" x 2-1/4"