Rites used flags (5)
I believe the answer is:
tires
'flags' is the definition.
(I've seen this in another clue)
'rites used' is the wordplay.
'used' is an anagram indicator.
'rites' anagrammed gives 'TIRES'.
(Other definitions for tires that I've seen before include "Becomes weary and in need of rest" , "Weakens" , "Wearies" , "Grows weary of rites" , "Exhausts" .)