Gas pump attachment (4)
I believe the answer is:
hose
'gas pump attachment' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hose that I've seen before include "Flexible pipe for liquid" , "One with doublet; a tube" , "Breeches (worn with a doublet)" , "plumbing connection" , "footwear" .)