The most common and most likely answer to this crossword clue is the 8 letter word ROLL-TOP
I've seen this crossword clue in The Guardian
R
O
L
L
-
T
O
P
More clues leading to the result ROLL-TOP
Buddy explains!
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.