It hasn't provided protective headgear (3-4)

I believe the answer is:

tin-hats

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'protective headgear' is the definition.
Although both the answer and 'headgear' are nouns, they are not in the same form of the noun.

'it hasn't provided' is the wordplay.
'provided' is an anagram indicator (I've seen 'provide' mean this).
'it'+'hasnt'='ithasnt'
'ithasnt' anagrammed gives 'TIN-HATS'.

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I've seen this clue in the Sydney Morning Herald.

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