Type of bolt secured by fan's shutters (7)

I believe the answer is:

louvers

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'shutters' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe there's a link between them I don't understand?

'type of bolt secured by fan's' is the wordplay.
'type of bolt' becomes 'u' (I can't explain this - if you can you should believe this answer much more).
'secured by' is an insertion indicator (inserted letters are held or secured).
'fan's' becomes 'lover's' ('lover' can be a synonym of 'fan').
'u' inserted inside 'lovers' is 'LOUVERS'.

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I've seen this clue in The Independent.

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