The heaters have water-filled steel tubes that zigzag in front of a reflective surface, which concentrates the sun's rays on the tubes.

这种加热器装有充满水的钢管，在反射面前头曲折布置，反射面将太阳光聚焦在钢管上。

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Supporting ring section is zigzag and is installed on the underside of the table. Top heating surface of induction cooker is on the same plane with table surface.

托环截面为之字型结构，该托环设置在桌子下表面，电磁炉发热的顶面与桌面平齐。

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Aside from the crunch of crampons on ice, the only sound is meltwater running over the glacier surface in a perfect zigzag stream.

BBC: The perfect trip: Switzerland