Ultimate consumer ensured confusion (3,4)
I believe the answer is:
end user
'ultimate consumer' is the definition.
(I've seen this before)
'ensured confusion' is the wordplay.
'confusion' indicates anagramming the letters.
'ensured' is an anagram of 'END-USER'.
(Other definitions for end user that I've seen before include "Being last to receive goods" , "Recipient of product sold" , "Receiver of product" , "One showing ultimate possession" , "Ensured (anag.)" .)