CMS Magnetics® 4" x 6" Green Magnetic Field Viewing Film, Fun!

Works grate my sun loved it

good

Bets value size wise on Amazon. However, this film is not very sensitive, so really only useful for viewing strong magnetic fields. Credit card magnetic strips are out.

Works great. Let's you see the field on anything magnetic.

Very helpful for tracking magnetic paths.

Pretty poor, arrived damaged despite packaging appearing fine. Film isn’t great quality. Better options out there.

Works as expected, cool item

I left a serious magnet on it for an hour or so- nothing happened. So I left it over night and nothing happened. Pointless.

Pratique et ludique pour montrer les champs magnétiques.

Not useful for daily things, but great for science experiments and entertainment. Probably the most useful thing about it is that it is basically 'x-ray vision' for the eddy current experiment where you drop a high-power cylinder magnet down an aluminum or copper tube and it drops very slowly. With this, you can 'see' the magnet through the tube as it falls. It's also fun to investigate refrigerator magnets and multi-magnet cubes, etc. With this little sheet, I accidentally discovered that putting my rare-earth block magnet on my fridge magnet made an obvious area where the NdFeB permanently overrode the poor little fridge magnet's field forever! :O It didn't stand a chance. "What can ferrite do against such reckless Teslas?" --fridge magnet, 2019-2019 Update: 2022 and mine still works great, although I haven't used it much. Surprised to see people saying they only work once. Maybe if you pinch the surface between two magnets, or scratch the back, you'll pop the little fluid areas and ruin them? Any way I've kept mine in its paperboard envelope and it seems safe in there.

No sirve

思ったより面白くなかった。

Es justo lo que esperaba, al principio la lámina es verde, al pasarle un iman se oscurece pero no por eso dejan de verse los campos magneticos. Te ahorras las limaduras de hierro en los experimentos.