It provided a cover on top of the hose (7)
I believe the answer is:
doublet
'cover on top of the hose' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'it provided a' is the wordplay.
I cannot quite understand how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is present in the answer.
The remaining letters 'double' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for doublet that I've seen before include "Formerly, a man's close-fitting jacket" , "Elizabethan man's jacket (worn with hose)" , "Old garment worn with hose" , "Padded jacket; pair" , "Close-fitting padded jacket of Tudor and Stuart England" .)