Note what e.g. Gloucester manufacturer uses up (6)
I believe the answer is:
tenner
'note' is the definition.
(a tenner is a 10 pound note)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for tenner that I've seen before include "Ten pound note (colloq.)" , "sounded by Peter Pears" , "Note - sounds like singer" , "UK banknote" , "A spot of money" .)