That is because a permanent magnet's maximum strength is dictated by the material it is made from, while an electromagnet's strength depends on the current passing through it.

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Of course, a device of that size also poses a number of problems, but Insound appears to have all those sorted out, with it employing a special "spongy material" that allows moisture to escape and prevent infection, and a magnet to actually remove the device from the ear.

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It's an incredibly sleek and solidly built device that won't leave us worried about durability, since it consists of aluminum on the sides and a soft-touch polycarbonate on the back that is quite similar to the material used on the 8X. (Unfortunately, it's also a fingerprint magnet.) Gorilla Glass 2 graces the display with the promise of preventing that beautiful screen from getting scuffed.

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