Green Magnetic Viewing Film 4x6 | Cool Magnets Science Kit | Magnetic Field Detector & Visual Aid for Physics Education | Ideal for Research & Magnetism Demonstrations

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.

Worked perfectly for detecting the magnetic fields in my new vehicle hub assembly! Also, fun to use on magnets and stuff. It's a very thin piece of material without and borders, but it works!

These sheets are very sensitive, although you do need to use them in a well-lit environment, as the images are inherently pretty dark. Also the film will leave ghost images behind indefinitely after you remove the magnet, so you might want to periodically degauss it by wiping it with a large refrigerator magnet that can hit the entire film in one pass. Sort of like erasing one of those old Magna Doodles. While it's certainly fun to just look at magnets, especially some of the complex ones that use alternating magnetic poles to have magnets that "turn off" by twisting 180 degrees so the magnetic fields cancel, etc. It's also handy for precisely locating magnets that are embedded inside objects, like the magnet in my laptop that holds the lid shut, or pinpointing exactly where the magnets are on cabinet doors so I know where to put a pad of felt to muffle the slam, etc.

It works, can identify poles of a magnet and identify hidden magnets, but requires a fairly strong magnet to make it work. It came out of package a nice green sheet, but as soon as you use it gets dark streaks all over. Still works, but not quite as magical as I was hoping. I was hoping to use it for wheel bearings with magnets in the race (for hall effect sensors), but I do not think it would be able to identify those very well (too weak of magnets).

Not sure why some reviews are so bad. It you want it to look like the picture, put some lights behind it. Product works better than I was expecting. item is a little small, but if you are not doing a demonstration and this is for personal use, its a perfect size. Using it in my living room with normal lighting I can clearly see the changes on the magnetic plastic. If you have a stronger magnet or move it fast across the plastic sheet, it will leave a haze trail that lasts a few seconds. Was kind of neat to find out the magnets I took out of some hard drives only have polarity on either side, the very center was dead and was showing nothing. Overall very happy with it.

We bought 2 of these as Wheel Bearing Check Tools to make sure any of the North/South Magnetic poles on an embedded Wheel Bearing that's also the Speed Sensor ring for an ABS system are okay from packaging and shipping damage- Once you place the Film on top of one of these bearings, the Magnetic sections in the seal just jump right out visibly, and you can spot if any of the tiny magnetic poles are damaged or are all okay before you start pressing the bearing into a hub assembly. Wish we'd known about these very inexpensive tools years earlier, since ABS type speed reading bearing systems only need a single magnet pole damaged to store a Trouble Light or warning light on your dash. Without the Film to show the magnetic poles, the seals look fine to the naked eye and you'd never know a bearing might have slight damage to its seal before you installed it.

Pratique et ludique pour montrer les champs magnétiques.

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.

while being bigger than most of the other on the market is is really weak. You will need a really string light to even see the patterns. and I paid €60 for this... :(