凹槽位于螺丝头 上，嵌槽凹设于凹槽的底部中央，而凸缘位于凹槽的外周缘。

The flute is located on the screw head, and the inserting recess is located at outer circumference of the flute.

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这类产品可带有在轧制过程中产生的凹痕、凸缘、槽沟或其他变形（钢筋）。

These products may have indentations, ribs, grooves or other deformations produced during the rolling process (reinforcing bars and rods).

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这类产品可带有在轧制过程中产生的凹痕、凸缘、槽沟或其他变形（钢筋）。

These products may have indentations, ribs, grooves or other deformations produced during the rolling process (reinforcing bars and rods).

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