Four Cubes in a Cube, or the famous Turner's Cube puzzle. Great souvenir and an exclusive gift is a real technical challenge for every experienced machinist. Manufactured from the single solid block of 6061 aluminum. There are five cubes, all separated. All inner cubes can be moved and rotated freely, but can't come out. Perfect brain teaser. The outer cube is 2" x 2" x 2", or 50mm x 50mm x 50mm. High quality, precise cut, very smooth and shiny surface, largest number-of-cubes to size ratio. Unseparated version of puzzle is available on demand. Made in Arizona, USA.