Pressing item is dull and inflexible (8)
I believe the answer is:
flatiron
'pressing item' is the definition.
(item for pressing clothes)
'dull and inflexible' is the wordplay.
'dull' becomes 'flat' (similar in meaning).
'and' says to put letters next to each other.
'inflexible' becomes 'iron' (I've seen this in another clue).
'flat'+'iron'='FLATIRON'
'is' is the link.
(Other definitions for flatiron that I've seen before include "household appliance" , "Fire-heated smoother" , "Old-fashioned clothes presser" , "that's no longer a pressing requirement" , "Antique household implement" .)