The most common and most likely answer to this crossword clue is the 8 letter word TURNKEYS
I've seen this crossword clue in The Daily Telegraph
T
U
R
N
K
E
Y
S
More clues leading to the result TURNKEYS
Buddy explains!

The straight part
We know that "Keepers" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case keepers = turnkeys.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.
What does TURNKEYS mean?
TURNKEYS noun- A warder or jailer/gaoler; keeper of the keys in a prison.
- To supply a turnkey product; to supply something fully assembled and ready to use