Small tool needed for footwear (4)
I believe the answer is:
shoe
'for footwear' is the definition.
(shoe is a kind of footwear)
'small tool needed' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'tool' becomes 'hoe' (hoe is a kind of tool).
'needed' means one lot of letters go next to another.
's'+'hoe'='SHOE'
(Other definitions for shoe that I've seen before include "Loafer, say" , "Winkle-picker, for example" , "Brogue, for example" , "pump, say" , "mule, perhaps?" .)