Calls, in our hearing, for wrenches (6)
I believe the answer is:
wrings
'wrenches' is the definition.
('wring' can be a synonym of 'wrench')
'calls in our hearing' is the wordplay.
'calls' becomes 'rings' ('ring' can be a synonym of 'call').
'in our hearing' shows a homophone (sound like).
'rings' sounds like 'WRINGS'.
'for' acts as a link.
(Other definitions for wrings that I've seen before include "Wrenches" , "Twists and squeezes, maybe hands in distress" , "Twists and squeezes to remove liquid" .)