Magne-Hinge, the newest product from masterful designers over at Nendo, lets you snap your glasses apart so you can mix-and-match components at whim.
Magnets are what keep all the components of your eyeglasses in place--the magne-hinges are strong enough to keep the temples and earpieces attached to a 0.8 mm carved titanium frame.
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As a specky guy myself, I love these. But sadly, as with many of Nendo's creations, the Magne-Hinge glasses are difficult to get outside of Japan, where they're being sold exclusively at Seibu Department Stores.