Punches ain't less brutal (4,4)

I believe the answer is:

nail sets

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'punches' is the definition.
I know nothing about this answer so I can't judge whether this works.

'ain't less brutal' is the wordplay.
'ain't less' anagrams to 'NAIL SETS'.
But, I am unsure how this is indicated.

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I've seen this clue in The Guardian.

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