LOVIMAG Super Strong Neodymium Disc Magnets with Epoxy Coating, Powerful Permanent Rare Earth Magnets 1.26 inch x 1/8 inch, Pack of 10

You ***can*** use these on tablet cases! I've attached 10 to the back of my tablet CASE with no problem with function of the tablet or the GPS system. Been on there for over 10 months with no damage to the tablet whatsoever. I got super frustrated not being able to find a tablet case that would sit without a "frame and all the crap associated with it" on a vertical steel surface (like a gym locker, refrigerator or where I work that has steel walls....)

Silly me forgot about physics. Don't stack the batteries. As I went to slide another one on, it FLEW out of my hand, and SLAMMED into the stack in the other causing is to pretty much explode. HUGE SPARKS, the magnet was just shards, but wasn't much to clean up since they all just got sucked back in. Besides me being not too smart, I have no complaints. I mostly use them to hang paint brushes to dry, tools, etc. Stronger than I thought they would be. Definitely recommend. Per the web: While stacking magnets can lead to a temporary boost in attraction, it’s important to note that there are physical limitations that prevent an infinite increase in strength. As magnets get closer to each other, their magnetic fields interact, resulting in repulsion rather than attraction. Thus, there is a limit to how many magnets can be stacked before the repulsion overpowers the attraction.

I am using these as a replacement for suction cups that always fail in my aquarium over time. They are sufficiently strong, can be doubled or tripled up if more strength is needed, and the coating protects the glass from getting scratched. I have re-purchased these several times and will continue to buy more as needed. I use clear gorilla glue to fasten them to the piece inside the tank, and one or two outside to hold them against the glass, depending on the strength I need. I have even glued them to suction cups to keep my filter tubes and heaters from detaching from the glass. Out of the box, these magnets seem frighteningly strong - too strong in fact. However, that is because all 10 are stacked together, amplifying their strength. To separate them, you can slide them apart, like sliding a card from a deck of playing cards. I have also found a plastic putty knife works quite well to separate them. WARNING - a stack of these can pick up a loose magnet from 6-8 inches away, with a frightening, finger pinching thwack! It can/will also shatter the magnet into very sharp magnetized shards. If ingested by a child or pet, these shards can cause fatal internal injuries. DO NOT be tempted to use any broken magnets pieces, and be sure to dispose of them safely.

I didn't buy these magnets to do anything exciting as some of these reviewers did. I just wanted to have magnets strong enough to hold a calendar on the refrigerator or anything else I wanted to stick there. They came in a cute little box with a block of Styrofoam that just fits the box and has a hole cut in the center to exactly fit the stack of magnets. There are some round stickers that fit the magnets, but I don't know why they are there. There are also thin spacers between each magnet. Still, getting the magnets apart can be dangerous as I was finally reduced to using a sharp knife to slice between them which was not at all safe or easy either, but it finally worked. And, yes, just one or two magnets will hole a calendar on the refrigerator depending on calendar size. Maybe three when you get to a later month in the year. Very good buy!

1. Adhesive strength is no where near 18lbs 2. Magnets are not the size advertised. They are .106 thick by 1.157 diameter 3. 2 of the 9 magnets were chipped inside the packaging 4. Would not order again