Standard partners getting off with sadists (5,3,7)

I believe the answer is:

stars and stripes

'standard' is the definition.
(the US flag - standard can mean a flag)

'partners getting off with sadists' is the wordplay.
'getting off with' indicates an anagram (off can mean inaccurate or wrong).
'partners' anagrammed with 'sadists' gives 'STARS AND STRIPES'.

(Other definitions for stars and stripes that I've seen before include "American flier" , "indications of rank" , "indicators of military rank" , "Standard" , "The US flag" .)

I've seen this clue in The Guardian.

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