Supporting part of garment, spare tights apt when elasticated (9,5)

I believe the answer is:

spaghetti strap

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

'garment spare tights apt when elasticated' is the wordplay.
'spare tights apt' can be anagrammed to 'SPAGHETTI STRAP'.
Though, I am not sure how the anagram is indicated.

'of' is the link.

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I've seen this clue in The Telegraph.

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