Implements in a suit (6)
I believe the answer is:
spades
I believe this clue is a double definition.
'implements' is the first definition.
(spade is a kind of implement)
'suit' is the second definition.
(playing card suit)
'in a' is the link.
(Other definitions for spades that I've seen before include "Digging tools and card suit" , "Suit in pack of cards" , "Digging implements" , "Does some groundwork" , "Black suit" .)