Auctioneers' mallets (6)
I believe the answer is:
gavels
'auctioneers' mallets' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for gavels that I've seen before include "Auctioneers' hammers" , "Mallets used by presiding officers" , "Mallets for auctioneers" , "Judges' mallets" .)