Case thickness: 12 mm.

表壳厚度：12毫米。

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Case thickness: 15 mm.

表壳厚度：15毫米。

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Case thickness of 0.001 to 0.012in. (0.03~0.30mm) is obtained, whereas for gas nitriding the case may be as thick as 0.025 in. (0.64mm).

液体渗氮可以获得厚度为0.001到0.012英寸（0.03~0.30mm）的硬化层，然而气体渗氮则能获得厚0.025英寸（0.64mm）的硬化层。

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Today's iPhone 5 doubles the processor performance again, stretches the astonishing Retina display to provide even more pixels, and shaves nearly another 20% off the case thickness to create a device that's unlike any other, yet builds seamlessly on previous generations.

BBC: News - Viewpoint: iPhone 5 proves Apple is still innovating - in its own way

The case added thickness and weight.

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While it isn't built into the hardware, it doesn't seem to add much to the weight or the thickness of the case and thus the device itself.

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