Glass does not have an earpiece but rather transmits sound through bone conduction.

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The bone conduction transducer allows the wearer to hear audio without the need for in-ear headphones - sound waves are instead delivered through the user's cheekbones and into the inner ear.

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To get navigation information to the wearer, the SWAN employs a pair of "bonephones" (also developed by Georgia Tech), which send sounds to the person using bone conduction, letting them keep their ears free to hear what's going on around them.

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Or even being spoken to you with a bone-conduction speaker.

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In 2005 and 2006, patients in McAllen received twenty per cent more abdominal ultrasounds, thirty per cent more bone-density studies, sixty per cent more stress tests with echocardiography, two hundred per cent more nerve-conduction studies to diagnose carpal-tunnel syndrome, and five hundred and fifty per cent more urine-flow studies to diagnose prostate troubles.

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