This Ferrofluid Display Cell is a fantastic way to demonstrate Ferrofluid with any age students. The strong 5.5" plastic display cell is completely sealed and resistant to breakage. Use the cell with any strong magnet to demonstrate the incredible properties of this amazing liquid. Demonstrate lines of force or show how charged particles stream into a star. Educational Innovations created these cells cooperatively with Ferrofluidics Corporation and is your sole source for them.Note: The Ferrofluid in the display cells is not the same as the bulk Ferrofluid.