From time to time I see a pickup truck like this one with one of those things behind the rear window. It’s basically an accessory that gives the appearance of “buttresses” like the ones on a Dodge Charger. (Picture.)
There has to be a technical name for that item. What is it?
Wouldn’t a cab spoiler also refer to what may be inside the cab on occasion as well?
The one pictured in the OP is not a spoiler, It’s merely a blind-spot extender. The one in don’t ask’s link has a little wingy thing which might exert some downforce, but the only practical use for either one is to provide a sunshade for the rear window. People buy them because they like the look.
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