How stupid of me to return this builder’s equipment (3)
I believe the answer is:
hod
'builder's equipment' is the definition.
(a hod is used for carrying bricks)
'how stupid of me to return' is the wordplay.
'how stupid of me' becomes 'd'oh' ('d'oh' is said after doing something stupid).
'to return' says the letters should be written backwards.
'doh' in reverse letter order is 'HOD'.
'this' is the link.
(Other definitions for hod that I've seen before include "A bricklayer's carrying pole" , "Carrier for a bricklayer" , "Brickie's carrier" , "Coal scuttle" , "Brick-carrier's holder" .)