The two times humans have reached the deepest part of the ocean, it required a foot-thick flawless metal sphere with barely enough internal space to sit down.

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In August 2011, Speth and his chief engineer finally broke through more than two meters of earth and reinforced concrete and the shelter's 278-millimeter-thick ceiling to emerge into a 40-square-meter space, divided into five interconnecting rooms by heavy metals doors.

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The conversion took five years, and involved removing the roof, more than 10 feet thick, with a diamond saw, as well as extracting interior walls to make space for the art.

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Internally, the Droid DNA is again a winner with its exclusive Qi wireless charging feature, but this does require some extra space, making the model 0.65mm thicker than the 9.08mm-thick X920d and X920e.

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