New models produced infrequently (6)
I believe the answer is:
seldom
'infrequently' is the definition.
(I've seen this in another clue)
'new models' is the wordplay.
'new' is an anagram indicator.
'models' is an anagram of 'SELDOM'.
'produced' acts as a link.
(Other definitions for seldom that I've seen before include "on rare occasions" , "Not 21" , "Only occasionally" , "Models (anag)" , "Once in a blue moon" .)