Material for brief performance on flute, say (10)

I believe the answer is:

fibreglass

'material' is the definition.
(fibreglass is a kind of material)

'brief performance on flute say' is the wordplay.
'performance' indicates anagramming the letters.
'on' says to put letters next to each other.
'flute say' becomes 'glass' (flute is a kind of glass).
'brief' is an anagram of 'fibre'.
'fibre'+'glass'='FIBREGLASS'

'for' acts as a link.

(Another definition for fibreglass that I've seen is " Material used as insulation or to reinforce plastics".)

I've seen this clue in The Daily Express.

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