Implements left in black stuff brought back (5)
I believe the answer is:
tools
'implements' is the definition.
(tool is a kind of implement)
'left in black stuff brought back' is the wordplay.
'left' becomes 'l' (common abbreviation).
'in' indicates putting letters inside.
'black stuff' becomes 'soot' (I've seen this in another clue).
'brought back' says the letters should be written backwards.
'l' going within 'soot' is 'sloot'.
'sloot' written backwards gives 'TOOLS'.
(Other definitions for tools that I've seen before include "Implements used to carry out particular functions" , "Hand implements" , "'A bad workman blames his . . . . .'" , "Implements used in one's job" , "Devices or implements, as of the trade" .)