What is the purpose of this large enclosure at O'Hare airport?

4yr ⋅ ⋅

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Already a top recruiting prospect (x-post from r/gifs)

11yr ⋅

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Poorly modified comic from poorlydrawnlines.com

11yr ⋅

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I've been seeing this S on a lot of cars recently. Anyone know what it is?

10yr ⋅

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