Each is a transparent sheath of plastic 17-metres long, mostly underwater, held in place by a floating collar.

每个都是17米长的塑胶套子，大部分淹没于水下，由一个浮动的环状装置固定住。

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Each is a transparent sheath of plastic 17-metres long, mostly underwater, held in place by a floating collar.

每个都是17米长的塑胶套子，大部分淹没于水下，由一个浮动的环状装置固定住。

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