The Consumer Product Safety Commission considers these small magnets, sometimes called rare-earth or neodymium magnets, to be dangerous. Though the magnets are meant for adults, kids have gotten a hold of them and swallowed them, which can cause devastating bowel injuries when the magnets attract inside of their digestive tracts.

The CPSC tried to get magnet companies to stop selling them voluntarily and when that didn't completely work, it went after them on two fronts: a lawsuit and a ban. Qu and other magnet sellers fought back, but after more than two years, Qu is the last one still battling.

Below are several videos that explain what Zen Magnets are, show how they're used and illustrate the fight between magnet companies and the federal CPSC.

This is one of the first videos Zen Magnets posted to YouTube:

Zen Magnets also sells colored magnet spheres called Neoballs:

After leading magnet company Buckyballs threatened Qu for claiming Zen Magnets were higher-quality than Buckyballs, Qu (that's him in the 3-D glasses) responded via video:

Continue for more videos, including some addressing the potential hazards.