Pop band appreciated fifty per cent off jacket and headwear (4,4)
I believe the answer is:
take that
'pop band appreciated fifty' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'per cent off jacket and headwear' is the wordplay.
I cannot quite understand how this works, but
'per' could be 'a' and 'a' is present in the answer.
'headwear' could be 'hat' (I've seen this before) and 'hat' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for take that that I've seen is " pop group".)