DIAMOND Cast Metal Puzzle from Hanayama Puzzles of Japan is both a delightful and tricky brain teaser puzzle. It consists of two diamond shaped pieces, which when joined together form a square. Objective is to rejoin the two pieces. Measures approximately 1.25 inches square and .50 inches thick. This is a really fascinating disentanglement brainteaser. DIAMOND Hanayama Puzzle is a NEW 2017 Design. Recommended for ages 13 to 105 years. NO force is used to solve. Forcing pieces may damage the puzzle !! Rated by the manufacturer as a level 1 difficulty (on a scale of 1 to 6 where 6 is the most challenging.) Difficulty level shown on the packaging. Your own experience could vary substantially. DIAMOND is part of a series of 55 plus very interesting and mentally provocative metal brain teasers from the Hanayama Puzzle Company. Some serious puzzlers refer to these as "disentanglement-style puzzles" as they involve taking something apart and then re-assembling. Re-assembly can also be a puzzle and may be equally as tricky. Reminder. NO FORCE is ever required to solve the puzzle. Just a series of clever moves.