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

Does what it says on the tin! Effective and simple. Great, easy, fast way to locate a hidden magnet in a phone case, electronic device, or whatever.

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.

I love this film, and plan on buying many more of it in the future! Now, its not incredibly sensitive, but it works great for my projects on magnetism in the lab. If you hold a small neodymium magnet near another of the same magnet, it may respond about 8 inches out. This film, will respond about 2 inches out. That should give you an idea of the sensitivity. One thing that I expect many people to get frustrated about, is the fact that once the magnet has come near, the magnetic particles in the film will stick to the last thing they caught. It will not revert back to the pure greenish color, unless you place it near a specially build magnet, that will tune everything back. I make magnets for different experiments, so I was easily able to build one for this purpose. Over all, this is actually one of my favorite toys in the lab! For this little 4" x 6" piece, I would have happily paid $40 for 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.

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).

I bought the following related items together, so I'm putting the reviews together as well for your convenience. A) < Magnetic Field Demonstrator, Student, Value Pack > > 1 star > Pro - cheap. > Con - filings too big & heavy to align with or indicate the flux lines, so you just get "indicators" that clumps together without revealing much insights. B) < CMS Magnetics® 4" x 6" Green Magnetic Field Viewing Film, Fun! > > 3 stars > Pro - a) it really does look very cool, & weird, & psychedelic; & b) shows magnetic strength. > Con - a) but it gives you little bang for the bucks (when including shipping); b) it doesn't show flux lines; c) thin so may be damaged if not careful. C) < American Educational Steric Demonstrator, For Magnetic Line of Force > > 2 stars > Pro - it sort of works, showing the magnetic flux lines. > Con - a) but it's overpriced for its quality; b) flimsily made with thin brittle plastic pieces glued together as if toddlers; c) pointers don't rotate well and are spaced too far, giving very low resolution; d) awkward to handle, & not designed well. D) < Dowling Magnets Mysterious Magnet Tube > > 4 stars > Pro - a) reasonably priced; & b) works surprisingly well showing the flux field. > Con - a) not as good as < 3B Scientific Three Dimensional Magnetic Field Lines Device, 140mm x 140mm x 120mm Size, 21mm Hole Diameter > ($174 as of 10/18/13), but doesn't cost as much either; b) without fluid to help counter gravity (like the expensive one above), flux lines droop. >>Conclusions: 1) For neat magnetic visual effects, get (B) of above; though methought overpriced, but still affordable. 2) For demonstrating magnetic flux lines, get (D) of above for its good value & say ~80% demonstrative effectiveness; unless you can afford the high quality alternative mentioned above. 3) Forget (A) & (C).

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.

This was fun to take around the house and check for hidden magnets. We used this as a teaching tool and opened the door to discussing polarization. Great value for the money.

Ok

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.

Works grate my sun loved it