The key element of the Magna Doodle is the magnetophoretic display panel. Each honeycombed cell of the lattice is filled with a thick liquid filled with tiny magnetic particles. The middle layer is latticed so that there is always an even distribution of the magnetic particles across the entire surface of the display. The liquid is designed so that the particles can be pulled through the liquid in response to magnetic force applied by the pen or eraser, but not due to gravity.