"Delivers," one puts, "at no extra charge" (4,4)

I believe the answer is:

sets free

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'delivers one' is the definition.
I can't judge whether this definition defines the answer.

'puts at no extra charge' is the wordplay.
'puts' becomes 'sets' (setting is a kind of putting).
'at' is a charade indicator (letters next to each other).
'no extra charge' becomes 'free' (I can't justify this - if you can you should believe this answer much more).
'sets'+'free'='SETS FREE'

Can you help me to learn more?

I've seen this clue in the Evening Standard.

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