In proper kit — a benefit from work (4)
I believe the answer is:
perk
'work' is the definition.
(thesaurus)
'in proper kit a benefit' is the wordplay.
'in' indicates the answer is hidden within the clue.
'PERK' can be found hidden inside 'proper kit benefit'.
'from' is the link.
(Other definitions for perk that I've seen before include "Incidental gain" , "Bonus" , "Informal goodie given on top of salary" , "A little extra" , "Tip" .)