Mess free magnetic field study - no need to clean up iron filings. The clear cube is filled with iron filings suspended in a solution, which makes it possible to view magnetic field patters easily by adding a magnet into the center of the cube (magnet is included). The patterns can be observed from all angles and easily manipulated with other magnets from the outside of the cube. Clear acrylic material also allows for overhead projection for whole groups to view. Dimensions: 3" cube