Device put into effect (9)
I believe the answer is:
implement
I believe this clue is a double definition.
'device' is the first definition.
(both can mean a tool)
'put into effect' is the second definition.
(I've seen this in another clue)
(Other definitions for implement that I've seen before include "appliance" , "Put into effect; tool" , "Perform" , "Put into action - utensil" , "Enforce, carry out" .)