Band roles reversed (5)
I believe the answer is:
strap
'band' is the definition.
(both can mean a strip of material)
'roles reversed' is the wordplay.
'roles' becomes 'parts' ('part' can be a synonym of 'role').
'reversed' is a reversal indicator.
'parts' reversed gives 'STRAP'.
(Other definitions for strap that I've seen before include "Narrow strip of leather" , "Strong band for binding luggage etc" , "Length or loop, of leather perhaps" , "Security device" , "Parts of a long piece of leather" .)