Sports gear, if set out, is a sporty adornment (2-6,7)

I believe the answer is:

go-faster stripes

'a sporty adornment' is the definition.
(eg a sports car might be decorated with them)

'sports gear if set out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'sports'+'gear'+'if'+'set'='sportsgearifset'
'sportsgearifset' anagrammed gives 'GO-FASTER STRIPES'.

'is' acts as a link.

(Another definition for go-faster stripes that I've seen is " Stickers on cars to make them look sportier".)

I've seen this clue in The Guardian.

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