Here is flush button.

这是冲水按钮。

youdao

He had slept little, but the knot of his red tie was predictably flush against the top button.

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The volume rocker is on the opposite side and the power button sits nearly flush with the tablet's frame on the upper-left corner.

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It's a little better than the design method used on the Droid DNA, where the power button is completely flush and quite difficult to press, though the buttons here still gave us trouble from time to time.

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