A hypercube
The net of a hypercube (one of the six regular polytopes in dimension 4) in the three-dimensional space: the colouring gives an idea of how to identify the square faces (in a similar way, we fold up the plane net of a three-dimensional cube to get the cube itself). Compare this image with other possible nets of the hypercube.
© matematita
The image belongs to the sections...:
Net of a hypercube (4D geometry)