Sunshade in an armoured car? (5)

I believe the answer is:

visor

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'sunshade' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for visor that I've seen before include "Sunscreen" , "Front piece of a helmet" , "Face armour" , "piece of armour" , "Eye shield" .)

I've seen this clue in the Evening Standard.

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