Article's enclosed for protective cover (5)
I believe the answer is:
apron
'protective cover' is the definition.
(I've seen this before)
'article's enclosed for' is the wordplay.
'article' becomes 'an' (indefinite article).
'enclosed' indicates putting letters inside.
'for' becomes 'pro' (I've seen this before).
'an' placed around 'pro' is 'APRON'.
(Other definitions for apron that I've seen before include "Projecting stage" , "Part of stage, boxing ring or airport terminal" , "Kitchen garment or airfield surface." , "Area for aircraft not in use" , "Area around aircraft hangar" .)