In a normal egg timer the sand always forms a flat cone onto whose tip the sand falls from above. This sand in this egg timer does the same, until you stand it in its wooden stand. Suddenly the sand forms a round hedgehog-like spiny structure. As soon as you lift the egg timer from the stand, the structure dissolves into the well-known cone shape.
The secret lies in the tiny, but strong neodymium magnet in the wooden base and in the fact that the sand consists of cast iron granules that are attracted to the magnet.
With a running time of approximately 30 seconds each time, it's not a very practical egg timer - but it's a fun and curious desk gadget for any home office or workspace.