Outer frame of galvanized, painted or stainless steel. Blades of galvanized or stainless steel with double sheet construction, silicon sealings. Maintenance-free stainless steel bearings and shafts.

外部框架为镀锌，涂漆或不锈钢。镀锌或不锈钢的风叶带双层结构。免维护的不锈钢轴套和转轴。

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Then, in 1964, a double sheet of plywood which might have belonged to the aircraft was found near Svalbard.

BBC: Hunt on for explorer's lost plane

That gave West Brom an unwanted record of 28 Premier League games without a clean sheet - and their hopes of a first double over Arsenal since 1961-62 suffered a further setback when the visitors levelled.

BBC: West Brom 2-2 Arsenal

Pre the introduction of the iPod Apple sold in the thirties (with a double digits valuation only because it carried a lot of cash on the balance sheet).

FORBES: Is Apple Worth $400 Or $900?