Secures what are on hand (5)
I believe the answer is:
nails
This could be a double definition.
'secures' is the first definition.
(I've seen this in another clue)
'are on hand' is the second definition.
'nails' can be an answer for 'hand' (thesaurus). I'm unsure of the 'are on' bit.
'what' is the link.
Can you help me to learn more?
(Other definitions for nails that I've seen before include "Part of body; hard as them" , "they may provide security for the board" , "Metal fasteners" , "Slain with metal pins" , "Cock's crest" .)