Container not very bright, we hear (4)
I believe the answer is:
pail
'container' is the definition.
(I know that pail is a type of container)
'not very bright we hear' is the wordplay.
'not very bright' becomes 'pale' (I've seen this in another clue).
'we hear' indicates a 'sounds like' (homophone) clue.
'pale' is a homophone of 'PAIL'.
(Other definitions for pail that I've seen before include "A bucket as for water" , "Container; sounds like dim" , "water-carrier" , "A bucket - the kind Jack and Jill used" , "Water carrier" .)